Good point RRR. Maybe that is why trannie input shafts are always a bit 'wobbly', and use a roller ball bearing, and not a needle bearing.... bell housing faces are gonna have a tolerance too.
Every dimension has a tolerance. Gear blanks for transmission are measured in .001 of a mm, not inch. Yet no matter how precise, there is still a tolerance even if it's 10 microns. My point to your point is "Amen", there is a tolerance.
I have never seen that spec in question measured. Ever.
