It’s hard break the glass ceiling : to wrap your head around new programming features you didn’t have before.
MySQL 4.1 has subqueries. And I can hardly find a use for them! I’ve gotten so used to thinking of SQL without subqueries that I can’t remember what I would need them for.
I’m sure I’ll find a use someday, when frustrated that I have to write an ugly solution to something that could be done more succinctly.
But this is how I feel with learning new programming languages, for example, where I find a language has Feature X, which I’ve never worked with before. My head is used to the limitation.