This whole discussion misses the point as it make such simplistic assumptions of what goes on in evaluating a candidate. With the software available now and/or simple human review, a school does not rate on these numbers as directly as it may seem during the "initial" (pre-interview) phase. Here you may have one of more evaluations, either pre-screen for secondary, post-screen by reader/adcom staff or formal review by adcom members. In any of these, you would get academically scored. That is, all the parts of your academic metrics are noted and you are given a score. The factors that can be taken into this would be
GPA (cGPA, sGPA aoGPA)
MCAT (whole, subsection, multiples)
Grade Trends
Weighting for school rank (prestige factor)
Weighting for credit loads (ie doing well in sGPA with high credit load vs. low credit load)
A simple (and common) system would be a score of 6 to 1, from outstanding to substandard (some will have 0 as in academically unqualified). 2 people may read your background and one with a 5 and one with 4. A computer algorithm doing this may come up with a more "precise" confidence score. Each school may weigh different factors differently and thus come up with different scores.
A similar process happens with all the other sections as well, but certainly more subjective. Schools will resort and score your experiences into such things as "healthcare experience" (ie all the clinical-related), nonclinical volunteering, research, etc. Say two people each read and score each category the school creates, two read PS, two secondary, etc. Each person has a score sheet with qualities/characteristics for the category and will evaluate you with a score and comments, again 6 to 1 from outstanding to substandard. They may do it as a whole score for that category or points for each characteristics.
Ultimately, all your sections will be evaluated, scored, and placed on a summary sheet for a total score. This what the committee will see as a whole, the summary. Not each member will read each application. Consider this your interview priority. Say 8 readers evaluate at 6 points each for 48 total. Everyone over 39 may get called for interview. As the cycle goes on and the slots fill up, that may slide up to 41 or 42. And depending on how/who is presenting your application, you may have a more forceful advocate and gets you a slot