While I don't have any information or authority to speak on the subject of healthcare accessibility in the Central Valley, whenever I hear a comment about fairness in the context of medical education, I like to remind myself and everyone else, that it's not about being fair to applicants, or even to medical schools. It's about being fair to, and doing what is best for, the patients. Right from the start of the admission process, the question should ideally be "What is best for the patients, and the people that we are trying to serve?". This is, from my limited understanding, how admissions committees evaluate applicants, and IMHO, should also be how we evaluate when or when not to implement programs like the fast-track. If this is a way to provide more care to the population in need, while still maintaining the quality of doctors, then the people in charge should try and make it happen.
I can speak on one other subject with a small amount of knowledge, and that's the existence of a similar program in Quebec. From what I've seen, the administrators I've talked to, etc. the 5yr MD students (fast-track) seem young at first, but end up being competent in the end. I think they grow up quickly. It's my personal feeling that it would be less stressful for the fast-track kids if they were required to take 1 more year in university to fully acclimatize, but that's a different story. Another example would be the existence of many European countries who train doctors right out of highschool.