diff --git a/fuzzers/007-timing/Makefile b/fuzzers/007-timing/Makefile
index 40e42a35..5734d78a 100644
--- a/fuzzers/007-timing/Makefile
+++ b/fuzzers/007-timing/Makefile
@@ -3,13 +3,13 @@
 PRJ?=picorv32
 PRJN?=8
 
-all: build/tilea.json
+all: build/timgrid-v.json
 
 clean:
 	rm -rf build
 	cd speed && $(MAKE) clean
 	cd timgrid && $(MAKE) clean
-	cd projects && $(MAKE) clean
+	cd projects/$(PRJ) && $(MAKE) clean
 
 speed/build/speed.json:
 	cd speed && $(MAKE)
@@ -17,10 +17,10 @@ speed/build/speed.json:
 timgrid/build/timgrid.json:
 	cd timgrid && $(MAKE)
 
-build/tilea.json: projects/$(PRJ)/build/tilea.json
+build/timgrid-v.json: projects/$(PRJ)/build/timgrid-v.json
 	mkdir -p build
-	cp projects/$(PRJ)/build/tilea.json build/tilea.json
+	cp projects/$(PRJ)/build/timgrid-v.json build/timgrid-v.json
 
-projects/$(PRJ)/build/tilea.json: speed/build/speed.json timgrid/build/timgrid.json
+projects/$(PRJ)/build/timgrid-v.json: speed/build/speed.json timgrid/build/timgrid.json
 	cd projects/$(PRJ) && $(MAKE) N=$(PRJN)
 
diff --git a/fuzzers/007-timing/README.md b/fuzzers/007-timing/README.md
index a7c79eb2..db5a98bc 100644
--- a/fuzzers/007-timing/README.md
+++ b/fuzzers/007-timing/README.md
@@ -13,10 +13,15 @@ Currently this document focuses exclusively on fabric timing delays.
 ## Quick start
 
 ```
-make
+make -j$(nproc)
 ```
 
-This will take a relatively long time (say 45 min) and generate build/tilea.json
+This will take a relatively long time (say 45 min) and generate build/timgrid-v.json.
+You can do a quicker test run (say 3 min) using:
+
+```
+make PRJ=oneblinkw PRJN=1 -j$(nproc)
+```
 
 
 ## Vivado background
diff --git a/fuzzers/007-timing/checksub.py b/fuzzers/007-timing/checksub.py
index 5387eaf1..86823805 100644
--- a/fuzzers/007-timing/checksub.py
+++ b/fuzzers/007-timing/checksub.py
@@ -58,7 +58,7 @@ def pds(Ads, s):
 
 
 def run(fns_in, sub_json=None, verbose=False):
-    assert len(fn_ins) > 0
+    assert len(fns_in) > 0
     # arbitrary corner...data is thrown away
     Ads, b = loadc_Ads_b(fns_in, "slow_max", ico=True)
 
diff --git a/fuzzers/007-timing/csv_flat2group.py b/fuzzers/007-timing/csv_flat2group.py
index a1defef2..a0f76f1d 100644
--- a/fuzzers/007-timing/csv_flat2group.py
+++ b/fuzzers/007-timing/csv_flat2group.py
@@ -35,7 +35,7 @@ def main():
     import argparse
 
     parser = argparse.ArgumentParser(
-        description='Substitute .csv to group correlated symbols')
+        description='Substitute .csv to group correlated variables')
 
     parser.add_argument('--verbose', action='store_true', help='')
     parser.add_argument('--strict', action='store_true', help='')
diff --git a/fuzzers/007-timing/csv_group2flat.py b/fuzzers/007-timing/csv_group2flat.py
index bba0cc5b..403b2991 100644
--- a/fuzzers/007-timing/csv_group2flat.py
+++ b/fuzzers/007-timing/csv_group2flat.py
@@ -3,8 +3,8 @@
 from timfuz import Benchmark, loadc_Ads_bs, load_sub, Ads2bounds, corners2csv, corner_s2i
 
 
-def gen_flat(fnin, sub_json, corner=None):
-    Ads, bs = loadc_Ads_bs([fnin], ico=True)
+def gen_flat(fns_in, sub_json, corner=None):
+    Ads, bs = loadc_Ads_bs(fns_in, ico=True)
     bounds = Ads2bounds(Ads, bs)
     zeros = set()
     nonzeros = set()
@@ -49,20 +49,19 @@ def run(fns_in, fnout, sub_json, corner=None, sort=False, verbose=False):
 
     with open(fnout, 'w') as fout:
         fout.write('ico,fast_max fast_min slow_max slow_min,rows...\n')
-        for fnin in fns_in:
-            #for name, corners in sortf(gen_flat(fnin, sub_json)):
-            for name, corners in gen_flat(fnin, sub_json, corner=corner):
-                row_ico = 1
-                items = [str(row_ico), corners2csv(corners)]
-                items.append('%u %s' % (1, name))
-                fout.write(','.join(items) + '\n')
+        #for name, corners in sortf(gen_flat(fnin, sub_json)):
+        for name, corners in gen_flat(fns_in, sub_json, corner=corner):
+            row_ico = 1
+            items = [str(row_ico), corners2csv(corners)]
+            items.append('%u %s' % (1, name))
+            fout.write(','.join(items) + '\n')
 
 
 def main():
     import argparse
 
     parser = argparse.ArgumentParser(
-        description='Substitute .csv to ungroup correlated symbols')
+        description='Substitute .csv to ungroup correlated variables')
 
     parser.add_argument('--verbose', action='store_true', help='')
     #parser.add_argument('--sort', action='store_true', help='')
@@ -75,7 +74,7 @@ def main():
     parser.add_argument('--out', default=None, help='output timing delay .csv')
     parser.add_argument(
         'fns_in',
-        default=None,
+        nargs='+',
         help='input timing delay .csv (NOTE: must be single column)')
     args = parser.parse_args()
     # Store options in dict to ease passing through functions
diff --git a/fuzzers/007-timing/projects/corner.mk b/fuzzers/007-timing/projects/corner.mk
index 3ed37050..f332d727 100644
--- a/fuzzers/007-timing/projects/corner.mk
+++ b/fuzzers/007-timing/projects/corner.mk
@@ -5,7 +5,7 @@ CORNER=slow_max
 ALLOW_ZERO_EQN?=N
 BADPRJ_OK?=N
 
-all: build/$(CORNER)/tilea.json
+all: build/$(CORNER)/timgrid-s.json
 
 run:
 	$(MAKE) clean
@@ -37,11 +37,11 @@ build/$(CORNER)/linprog.csv: build/$(CORNER)/leastsq.csv build/grouped.csv
 
 build/$(CORNER)/flat.csv: build/$(CORNER)/linprog.csv
 	# Take separated variables and back-annotate them to the original timing variables
-	python3 $(TIMFUZ_DIR)/csv_group2flat.py --sub-json build/sub.json --corner $(CORNER) --sort --out build/$(CORNER)/flat.csv.tmp build/$(CORNER)/linprog.csv
+	python3 $(TIMFUZ_DIR)/csv_group2flat.py --sub-json build/sub.json --corner $(CORNER) --out build/$(CORNER)/flat.csv.tmp build/$(CORNER)/linprog.csv
 	mv build/$(CORNER)/flat.csv.tmp build/$(CORNER)/flat.csv
 
-build/$(CORNER)/tilea.json: build/$(CORNER)/flat.csv
+build/$(CORNER)/timgrid-s.json: build/$(CORNER)/flat.csv
 	# Final processing
 	# Insert timing delays into actual tile layouts
-	python3 $(TIMFUZ_DIR)/tile_annotate.py --tile-json $(TIMFUZ_DIR)/timgrid/build/timgrid.json build/$(CORNER)/flat.csv build/$(CORNER)/tilea.json
+	python3 $(TIMFUZ_DIR)/tile_annotate.py --timgrid-s $(TIMFUZ_DIR)/timgrid/build/timgrid-s.json --out build/$(CORNER)/timgrid-vc.json build/$(CORNER)/flat.csv
 
diff --git a/fuzzers/007-timing/projects/project.mk b/fuzzers/007-timing/projects/project.mk
index 7e2b4f1f..dc29c28e 100644
--- a/fuzzers/007-timing/projects/project.mk
+++ b/fuzzers/007-timing/projects/project.mk
@@ -10,23 +10,19 @@ RREF_CORNER=slow_max
 ALLOW_ZERO_EQN?=N
 BADPRJ_OK?=N
 
-TILEA_JSONS=build/fast_max/tilea.json build/fast_min/tilea.json build/slow_max/tilea.json build/slow_min/tilea.json
+TIMGRID_VCS=build/fast_max/timgrid-vc.json build/fast_min/timgrid-vc.json build/slow_max/timgrid-vc.json build/slow_min/timgrid-vc.json
 
-all: build/tilea.json
+all: build/timgrid-v.json
 
 # make build/checksub first
-build/fast_max/tilea.json: build/checksub
+build/fast_max/timgrid-vc.json: build/checksub
 	$(MAKE) -f $(TIMFUZ_DIR)/projects/corner.mk CORNER=fast_max
-build/fast_min/tilea.json: build/checksub
+build/fast_min/timgrid-vc.json: build/checksub
 	$(MAKE) -f $(TIMFUZ_DIR)/projects/corner.mk CORNER=fast_min
-build/slow_max/tilea.json: build/checksub
+build/slow_max/timgrid-vc.json: build/checksub
 	$(MAKE) -f $(TIMFUZ_DIR)/projects/corner.mk CORNER=slow_max
-build/slow_min/tilea.json: build/checksub
+build/slow_min/timgrid-vc.json: build/checksub
 	$(MAKE) -f $(TIMFUZ_DIR)/projects/corner.mk CORNER=slow_min
-fast_max: build/fast_max/tilea.json
-fast_min: build/fast_min/tilea.json
-slow_max: build/slow_max/tilea.json
-slow_min: build/slow_min/tilea.json
 
 $(SPECIMENS_OK):
 	bash generate.sh $(subst /OK,,$@) || (if [ "$(BADPRJ_OK)" != 'Y' ] ; then exit 1; fi; exit 0)
@@ -76,6 +72,6 @@ build/checksub: build/grouped.csv build/sub.json
 	python3 $(TIMFUZ_DIR)/checksub.py --sub-json build/sub.json build/grouped.csv
 	touch build/checksub
 
-build/tilea.json: $(TILEA_JSONS)
-	python3 $(TIMFUZ_DIR)/tile_combine.py --out build/tilea.json $(TILEA_JSONS)
+build/timgrid-v.json: $(TIMGRID_VCS)
+	python3 $(TIMFUZ_DIR)/timgrid_vc2v.py --out build/timgrid-v.json $(TIMGRID_VCS)
 
diff --git a/fuzzers/007-timing/rref.py b/fuzzers/007-timing/rref.py
index e160768c..fedcfef5 100644
--- a/fuzzers/007-timing/rref.py
+++ b/fuzzers/007-timing/rref.py
@@ -29,7 +29,7 @@ class State(object):
         # known zero delay elements
         self.drop_names = set(drop_names)
         # active names in rows
-        # includes sub symbols, excludes symbols that have been substituted out
+        # includes sub variables, excludes variables that have been substituted out
         self.base_names = set(self.names)
         self.names = set(self.base_names)
         # List of variable substitutions
@@ -173,10 +173,10 @@ def state_rref(state, verbose=False):
         rowdsf = row_sym2dsf(rowsym, names)
 
         state.subs[group_name] = rowdsf
-        # Add the new symbol
+        # Add the new variables
         state.names.add(group_name)
-        # Remove substituted symbols
-        # Note: symbols may appear multiple times
+        # Remove substituted variables
+        # Note: variables may appear multiple times
         state.names.difference_update(set(rowdsf.keys()))
         pivot_name = names[row_pivot]
         state.pivots[group_name] = pivot_name
diff --git a/fuzzers/007-timing/solve_leastsq.py b/fuzzers/007-timing/solve_leastsq.py
index d77acd2d..db22b168 100644
--- a/fuzzers/007-timing/solve_leastsq.py
+++ b/fuzzers/007-timing/solve_leastsq.py
@@ -160,11 +160,15 @@ def main():
     parser.add_argument('--corner', required=True, default="slow_max", help='')
     parser.add_argument(
         '--out', default=None, help='output timing delay .json')
-    parser.add_argument('fns_in', nargs='+', 'timing3.csv input files')
+    parser.add_argument('fns_in', nargs='+', help='timing3.csv input files')
     args = parser.parse_args()
     # Store options in dict to ease passing through functions
     bench = Benchmark()
 
+    fns_in = args.fns_in
+    if not fns_in:
+        fns_in = glob.glob('specimen_*/timing3.csv')
+
     sub_json = None
     if args.sub_json:
         sub_json = load_sub(args.sub_json)
@@ -173,7 +177,7 @@ def main():
         timfuz_solve.run(
             run_corner=run_corner,
             sub_json=sub_json,
-            fns_in=args.fns_in,
+            fns_in=fns_in,
             corner=args.corner,
             massage=args.massage,
             outfn=args.out,
diff --git a/fuzzers/007-timing/solve_linprog.py b/fuzzers/007-timing/solve_linprog.py
index 6a27ac4c..d22e14d1 100644
--- a/fuzzers/007-timing/solve_linprog.py
+++ b/fuzzers/007-timing/solve_linprog.py
@@ -216,7 +216,7 @@ def main():
             run_corner=run_corner,
             sub_json=sub_json,
             sub_csv=args.sub_csv,
-            fn_in=fn_in,
+            fns_in=fns_in,
             corner=args.corner,
             massage=args.massage,
             outfn=args.out,
diff --git a/fuzzers/007-timing/tile_annotate.py b/fuzzers/007-timing/tile_annotate.py
index 7e87f2fa..ffc07a21 100644
--- a/fuzzers/007-timing/tile_annotate.py
+++ b/fuzzers/007-timing/tile_annotate.py
@@ -9,50 +9,24 @@ import time
 import json
 
 
-def run(fnin, fnout, tile_json_fn, verbose=False):
+def run(fns_in, fnout, tile_json_fn, verbose=False):
     # modified in place
     tilej = json.load(open(tile_json_fn, 'r'))
 
-    Ads, bs = loadc_Ads_bs([fnin], ico=True)
-    bounds = Ads2bounds(Ads, bs)
+    for fnin in fns_in:
+        Ads, bs = loadc_Ads_bs([fnin], ico=True)
+        bounds = Ads2bounds(Ads, bs)
 
-    pipn_net = 0
-    pipn_solved = [0, 0, 0, 0]
-    pipn_covered = [0, 0, 0, 0]
-    wiren_net = 0
-    wiren_solved = [0, 0, 0, 0]
-    wiren_covered = [0, 0, 0, 0]
+        for tile in tilej['tiles'].values():
+            pips = tile['pips']
+            for k, v in pips.items():
+                pips[k] = bounds.get('PIP_' + v, [None, None, None, None])
 
-    for tile in tilej['tiles'].values():
-        pips = tile['pips']
-        for k, v in pips.items():
-            pips[k] = bounds.get('PIP_' + v, [None, None, None, None])
-            pipn_net += 1
-            for i in range(4):
-                if pips[k][i]:
-                    pipn_solved[i] += 1
-                if pips[k][i] is not None:
-                    pipn_covered[i] += 1
+            wires = tile['wires']
+            for k, v in wires.items():
+                wires[k] = bounds.get('WIRE_' + v, [None, None, None, None])
 
-        wires = tile['wires']
-        for k, v in wires.items():
-            wires[k] = bounds.get('WIRE_' + v, [None, None, None, None])
-            wiren_net += 1
-            for i in range(4):
-                if wires[k][i]:
-                    wiren_solved[i] += 1
-                if wires[k][i] is not None:
-                    wiren_covered[i] += 1
-
-    for corner, corneri in timfuz.corner_s2i.items():
-        print('Corner %s' % corner)
-        print(
-            '  Pips: %u / %u solved, %u / %u covered' %
-            (pipn_solved[corneri], pipn_net, pipn_covered[corneri], pipn_net))
-        print(
-            '  Wires: %u / %u solved, %u / %u covered' % (
-                wiren_solved[corneri], wiren_net, wiren_covered[corneri],
-                wiren_net))
+    timfuz.tilej_stats(tilej)
 
     json.dump(
         tilej,
@@ -68,13 +42,19 @@ def main():
     parser = argparse.ArgumentParser(
         description=
         'Substitute timgrid timing model names for real timing values')
-    parser.add_argument('--tile-json', default='tiles.json', help='')
     parser.add_argument(
-        'fnin', default=None, help='Input flattened timing csv (flat.json)')
-    parser.add_argument('fnout', default=None, help='output tile .json')
+        '--timgrid-s',
+        default='../../timgrid/build/timgrid-s.json',
+        help='tilegrid timing delay symbolic input (timgrid-s.json)')
+    parser.add_argument(
+        '--out',
+        default='build/timgrid-vc.json',
+        help='tilegrid timing delay values at corner (timgrid-vc.json)')
+    parser.add_argument(
+        'fn_ins', nargs='+', help='Input flattened timing csv (flat.json)')
     args = parser.parse_args()
 
-    run(args.fnin, args.fnout, args.tile_json, verbose=False)
+    run(args.fn_ins, args.out, args.timgrid_s, verbose=False)
 
 
 if __name__ == '__main__':
diff --git a/fuzzers/007-timing/timfuz.py b/fuzzers/007-timing/timfuz.py
index 45569ed2..581de3a0 100644
--- a/fuzzers/007-timing/timfuz.py
+++ b/fuzzers/007-timing/timfuz.py
@@ -665,20 +665,20 @@ def load_sub(fn):
     return j
 
 
-def row_sub_syms(row, sub_json, strict=False, verbose=False):
+def row_sub_vars(row, sub_json, strict=False, verbose=False):
     if 0 and verbose:
         print("")
         print(row.items())
 
-    delsyms = 0
+    delvars = 0
     for k in sub_json['drop_names']:
         try:
             del row[k]
-            delsyms += 1
+            delvars += 1
         except KeyError:
             pass
     if verbose:
-        print("Deleted %u symbols" % delsyms)
+        print("Deleted %u variables" % delvars)
 
     if verbose:
         print('Checking pivots')
@@ -750,7 +750,7 @@ def run_sub_json(Ads, sub_json, strict=False, verbose=False):
             print('Row %u w/ %u elements' % (rowi, len(row)))
 
         row_orig = dict(row)
-        row_sub_syms(row, sub_json, strict=strict, verbose=verbose)
+        row_sub_vars(row, sub_json, strict=strict, verbose=verbose)
         nrows += 1
         if row_orig != row:
             nsubs += 1
@@ -817,3 +817,33 @@ def corners2csv(bs):
     assert len(bs) == 4
     corners = ["None" if b is None else str(b) for b in bs]
     return ' '.join(corners)
+
+
+def tilej_stats(tilej):
+    stats = {}
+    for etype in ('pips', 'wires'):
+        tm = stats.setdefault(etype, {})
+        tm['net'] = 0
+        tm['solved'] = [0, 0, 0, 0]
+        tm['covered'] = [0, 0, 0, 0]
+
+    for tile in tilej['tiles'].values():
+        for etype in ('pips', 'wires'):
+            pips = tile[etype]
+            for k, v in pips.items():
+                stats[etype]['net'] += 1
+                for i in range(4):
+                    if pips[k][i]:
+                        stats[etype]['solved'][i] += 1
+                    if pips[k][i] is not None:
+                        stats[etype]['covered'][i] += 1
+
+    for corner, corneri in corner_s2i.items():
+        print('Corner %s' % corner)
+        for etype in ('pips', 'wires'):
+            net = stats[etype]['net']
+            solved = stats[etype]['solved'][corneri]
+            covered = stats[etype]['covered'][corneri]
+            print(
+                '  %s: %u / %u solved, %u / %u covered' %
+                (etype, solved, net, covered, net))
diff --git a/fuzzers/007-timing/timgrid/Makefile b/fuzzers/007-timing/timgrid/Makefile
index af0a72da..30458303 100644
--- a/fuzzers/007-timing/timgrid/Makefile
+++ b/fuzzers/007-timing/timgrid/Makefile
@@ -5,7 +5,7 @@ build/timgrid.txt: generate.tcl
 	cd build && vivado -mode batch -source ../generate.tcl
 
 build/timgrid.json: build/timgrid.txt
-	cd build && python3 ../tile_txt2json.py --speed-json ../../speed/build/speed.json timgrid.txt timgrid.json
+	cd build && python3 ../tile_txt2json.py --speed-json ../../speed/build/speed.json timgrid.txt timgrid-s.json
 
 clean:
 	rm -rf build
diff --git a/fuzzers/007-timing/tile_combine.py b/fuzzers/007-timing/timgrid_vc2v.py
similarity index 92%
rename from fuzzers/007-timing/tile_combine.py
rename to fuzzers/007-timing/timgrid_vc2v.py
index 940d628f..8c188d81 100644
--- a/fuzzers/007-timing/tile_combine.py
+++ b/fuzzers/007-timing/timgrid_vc2v.py
@@ -5,6 +5,7 @@ import os
 import time
 import json
 from collections import OrderedDict
+import timfuz
 
 corner_s2i = OrderedDict(
     [
@@ -77,6 +78,7 @@ def check_corner_minmax(tilej, verbose=False):
     print('Checking for min/max consistency')
     checks = 0
     bad = 0
+
     for tilev in tilej['tiles'].values():
 
         def process_type(etype):
@@ -102,7 +104,10 @@ def check_corner_minmax(tilej, verbose=False):
 
         process_type('pips')
         process_type('wires')
-    print('minmax: %u / %u bad' % (bad, checks))
+
+    print('')
+    print('minmax: %u / %u pairs bad pairs adjusted' % (bad, checks))
+    timfuz.tilej_stats(tilej)
 
 
 def check_corners_minmax(tilej, verbose=False):
@@ -127,8 +132,9 @@ def main():
 
     parser = argparse.ArgumentParser(
         description='Combine multiple tile corners into one .json file')
-    parser.add_argument('--out', required=True, help='Combined .json file')
-    parser.add_argument('fnins', nargs='+', help='Input .json files')
+    parser.add_argument(
+        '--out', required=True, help='Combined timgrid-v.json files')
+    parser.add_argument('fnins', nargs='+', help='Input timgrid-vc.json files')
     args = parser.parse_args()
 
     run(args.fnins, args.out, verbose=False)
diff --git a/fuzzers/007-timing/timing_txt2csv.py b/fuzzers/007-timing/timing_txt2csv.py
index 3f0e62af..0ba2b36d 100644
--- a/fuzzers/007-timing/timing_txt2csv.py
+++ b/fuzzers/007-timing/timing_txt2csv.py
@@ -1,11 +1,9 @@
 #!/usr/bin/env python3
 
 from timfuz import Benchmark, A_di2ds
-import numpy as np
 import glob
 import math
 import json
-import sympy
 import sys
 from collections import OrderedDict