Okay, so here's an old thing I did that is critical to understanding OOTP overall ratings. I realize now in reading it that I explain what I did in a confusing way, so here's a recap. I made a left handed batting "perfectly average" 50 potential player with no splits. Then I fiddled around with his versus left handed pitching ratings (the weak side of his platoon that you probably will bench him for anyway), leaving the ones that matter much more, his versus RHP ratings, the same. It was surprising how much the overall potential changed. If you want to really understand OOTP ratings, you need to understand this. Because it's me, it's wordy and confusing at times with a bunch of numbers. But read it. I'm happy to talk about it in slack with anyone. Understanding how splits and overall pot ratings work, if you don't already, will make you better at OOTP.
Less math, more examples of the above study.