krestez if i recall back when someone gave him a difficult endgame position he looked at it and ignored it. i personally thought he was afraid to answer it, because he could go wrong. so yes in my personal opinion he is totally a patzer.
but thats my opinion i might be wrong.
I think you stop being a patzer when you start playing decent positional moves, when you understand all the basic concepts and stop losing pieces to 2-3 moves tactics. And that might be somewhere around 1700-1800. After that, you're an amateur, but not patzer. At least you have some sort of idea of what you're doing on the board.
well even plus 2000 player often blunder strategically , i really would think 2400 is the mark when someone isnt a patzer anymore.
I said decent. That doesn't mean you don't blunder. It means you have some sort of idea about positional play and you at least know how to evaluate a position.
And... 2400? Really? So the well-respected coach NM Dan Heisman is totally a patzer lol.