Originally Posted by Leisesturm

I doubt it. 2.5mm probably just exceeds the manufacturing tolerance for all but the best of the best components. Your cranks are mismatched by that much right now and you don't even notice. And as long as I am here I will observe that the 2.94% loss of torque going to the shorter cranks is not easily compensated for by downshifting since few clusters have less than a 9% change between gears. It's even bigger at the extremes. Seems to me that headwinds and climbing are the places where one would be least likely to want shorter cranks.