Originally Posted by terrymorse

Thanks, but I'm still not seeing it.

I can't see how rolling resistance changes when the wheel's angle changes.. "Grip" is a function of the compound in the rubber, which doesn't change.

Rolling resistance is produced by the deflection-return of rubber. That deflection-return ought to be equivalent whether the wheel is upright or leaning.

RR laboratory tests are done with constant conditions because they are repeatable across multiple tests and tires, not because they are "ideal".