Well scientifically speaking, no thats impossible. If two systems are exactly identical, then...well they're identical. The however is, you can have two setups: as and example: 05 magura water bleed pistons aligned perfectly try-all croco's harsh grind standard lever Trialtech rim One could have a contaminated rim, one could have a contaminated pad, one could have a small leak on the hoses, one person's finger could be stronger than the next... it goes on and on. I guess the reality in what your asking is two people can have seemingly the same brake setup, but one can work and the other cant EDIT: Just re-read your question again. I'd say if the setup didn't change and you had two brand new sets of pads, put one on, then change it, it wouldn't make a difference On my mod I went through so many different pads before deciding to go disc. Now on stock, back to maguras, and i've found coustsinks actually working this time, instead of not really holding on my mod. You just have to keep trying, change rims next time to something different and see if that holds better, source a different grinding disc and see if the composition of the disc is different...