There's a great player in my area that's rated at 4.0 (USTA computer rating) that didn't start until he was in his mid-twenties. Excellent mobility, not-so-pretty strokes, but amazing consistency and shot placement.
I ended up playing him in the semi's of a recent tournament and got pasted. He made two unforced errors the entire match - when they're that few, you can count them easily.
I played played a lot growing up in Florida - academy ladders, high school team, USTA tournaments, and team tennis. Now in my late twenties, I'm only competitive up into th 3.5 ranks. I've got "pretty" strokes, but they require a ton of footwork to pull off. It almost feels like a liability now - I can play with the 4.0's on our USTA teams, but once the rally gets long my feet simply give out and it's over. Point after point like that.
I'd actually love to have the simple strokes most of the guys who started as adults have.