I voted no because O Chem grade distributions vary widely from one class section to the next. At my school there were 4 sections for O chem I & 3 sections for O chem II this year. I chose what was reputed to be the hardest section for each semester, the first time because it was the only option to fit with my schedule, the second time because I ain't afraid of nothing. Granted that arguably shows poor decision-making on my part, but obviously not everyone can choose the easy section. The "hard" prof. made half of his exams ungodly difficult, while making the other normalish or even easy (compared to the other profs' exams).
In my second semester of O chem, there was a single A (that one guy that just proves it's doable & that I didn't try hard enough), no A-, 5 B+'s, 4 B's. I don't remember lesser grades than that as I didn't consider anyone with less than a B to be competition, but I recall the distribution was bimodal, with the larger peak being a tight group around C-. The mean score for the class was 71% (after curving). More than 1/3 of the class got failing grades. Meanwhile, in the easy class, there were a handful of A's & A-'s, few D's & F's, & a mean score of ~78%. So the easy class had a rather normal distribution.
I admit I had first pickin's at which section I wanted, & I chose wrongly (& I'd do it again too!!), but the majority of students got to register after the easy class had filled. They didn't have the luxury. Most of them weren't premeds, of course, but the entire grade spectrum was affected. I have no doubt that I would've gotten an A in the easy class, as would most of the students that scored B+'s or B's in my section.
I'm not suggesting Phys, Bio, or G Chem are necessarily more standardized. There could be significant variation in those too, it all depends on how difficult the professor wants to make the exams. Although, at my school, all bio classes are always curved to a 75% mean score as a department rule. Bio prof's will get reprimanded for making their tests too easy, but I know this isn't the case everywhere.
The MCAT is the great equalizer.
