Let's go through this in a couple points
1) Yes, it is not easy at all to find schools giving out information publically about their MCAT cut offs. U of Utah is a relative exception and even that isn't some ground breaking statement(almost nobody with a sub section 7 MCAT score is getting into medical school). Having gone through the process of calling many schools about such policies and talking to ADCOMs I know personally about their thoughts and how their schools view MCAT's and scores here are some thoughts I have collected and gathered from all this.
a) Schools don't like making public cut offs because they don't want to exclude the rare applicant who might be worth consideration below a cut off consideration(particularly URMs). Emory is an example of a school that cites a 27 is a minimum: they can do this because there simply aren't going to be worthwhile candidates to a school like that with a 26 or lower MCAT. This again though is more an exception than a rule.
b) These things are incredibly subjective as well. ADCOMs within a school themselves have different views on these things. A good example is how schools view multiple MCAT scores. Many schools average. Many don't have any official policy. Many schools that don't say they average have individual ADCOMs that will in their evaluation. But by and large a school will account for the fact the MCAT had to be taken twice by an applicant. How they will account for that will vary tremendously and honestly is hard to predict even for ADCOMs. Having called schools as an example asking how they view multiple MCATs: I can tell you calling the same school more than once I have gotten completely different answers about whether or not they will average the scores. This kind of highlights how much of a subjective process it is and why you don't want to open yourself up to idiosyncratic interpretation with multiple MCAT scores if you don't have to.
c) what is most likely is schools will use the highest MCAT score for their class profile stats. This is part of why you will see so many schools give lip service of "We'll use the highest score" when people on here call about how schools interpret multiple MCAT scores. They have every incentive to tell you they'll use the latest one; its in their best interests for many reasons.
d) 10th/90th percentile stats in MSAR are very valuable like you said yes. Phone calls to schools? They can vary in their value tremendously and should hardly be taken as gospel. Like I said, call the same school twice, you can get very different answers on the same question.
e) Having talked to ADCOMs I know personally and those on this site I really haven't gotten the idea of an 8 subsection being any real red flag at lower tier schools at all. In fact, 8 is often what I see as the cut off for acceptable from those I've talked to at lower tiers. Are there ADCOMs who will have problems with a 8? Yes they exist. But I'd be very hesitant to tell someone with a 8 who has a 31+ type score retake because of the 8. Not only is the 8 likely to be fine at many schools, you run the risk of doing worse which will really hurt your app. I am however willing to buy the idea an 8 science section from what I've gathered is more hazardous than that in verbal. There are schools like G'town that explicitly will state an 8 science score is not competitive while for verbal they will only say that with a 7 or lower.
As for a 33 being too high for a retake I'll give a couple things to consider
a) There is an ADCOM gyngyn on here who will tell people those who retake these 35+ type high scores automatically will get rejected at his school. I'd imagine his is hardly the only school with such a policy. SO yes, that should tell you right off the bat retaking high scores is often seen as a red flag that can in some schools be lethal.
b) As for the idea of retaking a 33 and scoring much higher always being beneficial I think this is worth reading.
http://forums.studentdoctor.net/thr...advice-to-assess-app-weakness-thanks.1074437/
Basically you have an applicant who didn't get into med school with a 42 MCAT score. They had previously retaken a 33. Pay close atetntion to all of Law2Doc's post in this thread who is an ADCOM. Basically his point is retaking the 33 was a mistake. The top schools can dismiss a high score very often if it is taken more than once. The lower tier schools are going to question the judgment of someone retaking a 33. Read his words exactly but it telegraphs things to schools you don't want in many cases retaking a 33 like this. In many ways retaking a 33 to a 42 put this applicant in a bind. The top schools can dismiss a 42 when it comes after multiple attempts. The lower tier schools are going to look at this as questionable decision making and as this applicant as low yield. Not an ideal situation and it led to the point this applicant didn't get in anywhere with one of the highest scores in the country. In many ways, going from a 33 to a 40+(very very rare and difficult) opens up doors at top schools potentially. But it can also close many at lower tiers. Whether the overall effect is to the applicants benefit will vary. And this is with a perfect retake and a best case scenario retake attempt.
c) MCAT retake statistics get published on the AAMC. I don't have the link on me but what you are talking about of going to a 33 to a 39+ is a very very rare thing. Happens 2-3% of the time. Nobody should bank on making that kind of improvement or assuming they will. 70-75% of people who retake a 33+ don't improve by 3+ points which is the bare minimum for what will constitute a worthwhile retake. We shouldn't base anything off outliers.
So bottom line, you have to consider the circumstances behind an MCAT retake very very carefully. Getting the same score or worse is a negative. Everybody should go into taking the MCAT only planning to take it once. The more you take it, the more you complicate things and open yourself up to risks.
