Today I swapped in the encoder wheel with more narrower "spokes."
First run (fairly short) looked pretty good:
Pulse-type filament monitor on pin e1stop, disabled, sensitivity 2.400mm/pulse, allowed movement 30% to 900%, check every 10.0mm, measured sensitivity 1.720mm/pulse, measured minimum 132%, maximum 143% over 282.0mm
I realized the pulse wasn't every 2.4mm, so I reset for closer to the 1.72 I was seeing here, and got these consistent results across a number of prints:
Pulse-type filament monitor on pin e1stop, disabled, sensitivity 1.710mm/pulse, allowed movement 30% to 900%, check every 6.0mm, measured sensitivity 1.713mm/pulse, measured minimum 82%, maximum 118% over 2541.8mm
I also modified the check to be every 6.0mm which should allow 3 pulses. The percentage "window" seems a bit larger, but I assume that is because the actual distance is allowed is shorter due to the narrow spokes and the 6mm distance.
Either way, this continues to be very repeatable!
Next tests (maybe tomorrow, but sadly my vacation is over) will be to cut the filament and see how it responds.