it's also been well documented that the 1000s of hs students across the U.S. who enter combined BS/MD or BA/MD programs never even take the MCAT (or a number of the prereqs) and still score really high on the boards....as do individuals with low MCATs who do SMPs, get into med school, and excel on the boards.
Check this out...
Are my MCAT scores predictive of my USMLE and medical school performance?
Much as the USMLE Step 1 score is an important variable in the residency application process, the MCAT score is given important weight in the medical school application process. Medical school admissions officers are faced with the daunting task of determining which students are the most qualified, comparing applicants from different institutions of different quality and grading schemes. The MCAT is meant as an objective and consistent means of comparison, though other factors are certainly considered in the medical school application process.
A 2007 meta-analysis evaluated the relationship between the MCAT and medical school performance. There was a
small to moderate correlation of MCAT performance with performance during the preclinical years, with the r value equal to roughly 0.39. There was also a correlation of certain subtests with preclinical performance, particularly the biological sciences subtest. The correlation was less strong between MCAT performance and performance during the clinical years. The writing subtest of the MCAT was shown to have no correlation with either performance during the preclinical years or the clinical clerkships.
A
small to moderate correlation was also found between MCAT and USMLE scores, with r values ranging from 0.38 to 0.60. This correlation was highest for USMLE Step 1. Among the different MCAT subsets, the
highest correlation was found for the biological sciences and verbal sections. There was near zero correlation between the writing subtest and USMLE scores.
http://www.usmleworld.com/Step1/step1_facts.aspx
So it seems biology and verbal are the only relevant portions in terms of success in med school (which makes sense since bio and organic are the foundations of how the body works, while gen chem and physics are focused more on scientific processes that are not really concerned with the body as much).