Yeah, but that's about where exceptional ATH growth tops out. LP and PER can, and often do, improve a lot more than that.
A player starting with a 25 ATH (high-high) and 25 LP or PER (high-high) is far, far, far more likely to increase to 65+ in LP or PER than in ATH. Given a good work ethic, probably 40% of the time the high-high LP or PER is going to get into the 80s or 90s. The ATH will do that exactly 0% of the time.