I disagree completely. Having spoken to someone who transferred medical schools (from a big name private school to a state school) for personal reasons, this individual holds that there is variance in the rigor with which schools train their medical students.
Speaking with my colleagues from other medical schools currently, I can *definitely* say that some courses are harder at certain institutions than others. I thought this was obvious, and should be intuitive:
If Harvard's lowest quartile ("a C student") had a 3.8 and a 515 MCAT, intrinsically you should know that candidate will do better at ICOM, and would likely be one of their top students. Why is a C (Harvard) student suddenly an A (ICOM) student? This intrinsically implies variance in academic rigor.
If PDs don't care about preclinical grades then it isn't really much of a motivator for students, since medical school's actual function is to match into a residency and not to inflate egos, right?