I know you said you measured them. For all we know you stuck lincolns head into the tread and drew a line with a sharpie! lol I assume you used the end of a digital caliper, or hope so.
You have to remember that your car has a lot going on under the surface. The small differences you dont think matter, really do!
I will prove it real quick. Once again, mechanical engineering kicks the shit out of shade tree logic.
The one on the left is a standard dia tire. 28" on the right is one 28.1" dia. Pshhhh .1" dat aint shiiiit right?
With the same gear ratios on both examples… look at what RPMS are needed at the crank to put out the same MPH per tire dia. 35RPM’s different to achieve the same MPH based on the roll out difference that lil .1" dia changed!
Sooo.
since your crank is of course not going to change RPM’s for each of the 4 unicorn tires you are putting on it… that will stay the same lets say 8285 Rpm like in my example.
tire 1 is on the front right 28" dia. Tire 2 is 28.1" on the left. tire 3 is brand new but such a great deal you got it anyway 28.2" on the left rear and the other 28" is on the right rear.
in a straight line the front and rear diffs will be slipping, and the center diff will be slipping to make up the 35 RPM difference. Now that needs to be computed in to the gear ratio for the diffs and all which I dont feel like going any deeper into this to prove myself.
Sure buzzing around an autocross track at limited speeds, might never know the difference by the seat of the pants, and you will prolly sell the car before the wear on the components will pop up. But it doesnt mean the little difference isnt going to hurt the car… you just dont know it!