Yeah, I really don't know why Dr. Camarrata said that about the BS section being most indicative of board scores. More often what you hear is that the Verbal score is MOST indicative of overall success in med school and of board performance (USMLE anyway).
Here is a study that correlates verbal skills (including SAT verbal and mcat) with board scores:
http://www.ncbi.nlm.nih.gov/pubmed/8615936?dopt=Abstract
So I was surprised when he said they don't even look at verbal. Either way, I'm sure there are different opinions...studying your butt off probably correlates with high board scores more than anything