Good topic. I generally consider myself a wed guy but on occasion I can do a Thursday/Sunday.
Being good at crosswords isn't about just memorizing the repeated clues (crosswordese). That isn't to say that practice doesn't make perfect though.
Doing crosswords daily opens up a different part of your mind. The more you do them the easier answers become. And generally, with the new york times at least, the answers aren't obscure but words or phrases we use every day.