I think you have the crux of it.
I would say create a fictional MAL, create a view in sortable player stats like I have in the pic, and sort any rating. I'd bet you'll find a lot of CR's that are grossly over
PR's(20 or more points difference). In addition, you'll find young and old players that have these drastic overages.
That may not be a bug in itself, and could be by design, but the inconsistency of how it's applied to players seems to be. One or the other is what I'm getting at.
Sorry if I'm confusing this further. Let me know if you need further clear as mud explanations.