I think those who believe the YP theory tend to be the same people who believe college admissions are a ranking game mostly based on GPA. In reality, GPA, albeit important, is just one factor among 13.
UCSB and UCR are the two UCs closest to using a numeric scoring (and ranking) during their admissions process. For this reason, officially UC says UCSB and UCR use a “hybrid” review process, while the other seven UCs use a pure holistic one.
From what I have learned, in a holistic process, they tend to use “buckets” instead of ranks when evaluating an applicant’s academics, if that makes any sense. Once two applicants are in the same GPA bucket, for example, any difference in GPA makes no further difference. What matters are differences in the rest 12 of the 13 factors.
Once you get an idea of how holistic review works, it’s not hard to understand, at least in principle, why an applicant with a higher GPA may be rejected but another with a slightly lower GPA is accepted.