PA defines the highest possible CA a player is able to achieve. If a player has a PA of 200 and he reaches it, then he has a CA of 200.
Does that mean he's a CA200-player all the time?
No, hidden attributes like consistency has a major impact how likely it is that a player is capable of playing at his actual CA-level.
This is why I think it's better to not know both of these values when you're playing this game. (Which is why they are hidden anyway)
So there is already much more dynamics included in the current model as some may think. It's just something which you can't get displayed on an excel sheet because it's within the game-code.
So down to my logic, CA is actually dynamic even when the number is the same, which makes PA also kinda dynamic