See 2002 NEC 310.4 (1)
No tolerances given.
Exactly the problem.
What tolerance is acceptable, 1", 1/2", .00025"?
It is imposable for one conductor to be exactly the same
length as another, there has to be a tolerance.
And to say one specific tolerance applies makes no sense. It would make more sense to say the tolerance is a certain percentage of the total length.
Anyway thats my two cents.