Edge Retention/Rolling Test Stand

[KnifeGrinders]

I am afraid for a rolled edge testing, the above repeatability target is unattainable just because the rolled edge scores within +/-50 BESS by its nature. It is sort of too springy.
In the meat factory we had to take 4 measurements in the same spot on each knife and average them because of that. Below are some example scores taken in the same spot (that was right under the V letter in the Victorinox etching on the blade) after 2 hours of cutting:

140
245
140
170

280
390
295
380

155
165
245
210

240
385
365
365

235
260
320
220

If we see that much dispersion in every single knife, no wonder in your case you see the dispersion among several knives.
I might be wrong, but I see value in two numbers: the amount of force needed to cause rolling, and then to cause inrepairable rolling.