Hi Ben,

A1) Yes. That will also correspond loosely with motor temps. When you see the temps increase sharply with one more pinion tooth instead of a predictable linear response, you'll also notice the car will start feeling soft about 1/2 way into the run. (but as you are practicing - always gear for best laptimes, and not automatically to the "breaking point" of the motor)

A2) Not really. Gearing down only 10% off of a competitive level isn't enough to cause issues. throw a 5.0 at it, and maybe that would be enough.