Quote - ...A python script would then determine which part of the tire is currently down,
and adjust the U offset accordingly.  (This would require a pre-measured
correlation between the offset and the rotation angle of the wheel.)

It should be possible to control the U offset using the rotation value of the tire or the wheel. 
The math could be done within the "morph" or in the material room.
I don't know the math, but I am quite sure it can be done.

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