The guy who's been playing the same $1/$2 game for years thinks he's a reg. He's not. He's a rec with a routine. His tendencies are locked in and he's never had a reason to fix them.

Why they do it

He wins enough to keep coming back. That's the problem. He's never been forced to adjust so he hasn't. Same bet sizing, same spots he slowplays, same spots he folds. Map him in the first orbit and you've got him figured out for the whole session.

The adjustment

Take mental notes early. By the time you're in a big pot with him you already know what his sizing means.

What it's worth

Once you've got him mapped, every big pot is a near-automatic decision. That's where you make your session.