d4f6b7bf03
Correcting the previous iteration's wording. It claimed on n=1 that disabling the periodic rescan "removes the freeze". With more runs that is too strong: the configuration is now clean at 210, 240 and 300 seconds and frozen at 60 on a fourth run. The tally across configurations: the heavy probe froze at 27, 45, 83, 183 and 255 seconds; the cheap probe with a 90 s rescan froze at 183; the cheap probe with no rescan is clean in three runs of four past 200 s. That is a real and large improvement in survival, but it is a change in probability rather than a fix, and the documentation now says so. The witness handled the frozen run correctly -- losses stop at t=45 and stalls are flagged from t=60 onward, with no contradiction between them. Separately, the candidate search was the last Python loop over eight million words and most of the remaining startup cost. Replaced with two numpy vector operations; 7250 candidates found and startup is no longer the bottleneck. Boot now dominates: about 190 s of title movie plus 35 s to flight against a 595 s turn cap leaves roughly 350 s of observation, so boot is the only remaining lever if longer windows are needed. Practical rule recorded: do not treat a single frozen run as evidence. Run, check the witness, discard the frozen ones and keep the clean ones -- about three in four are usable now, which is workable where it previously was not.