Immediate feedback does suffer, but errors have a way of being pointed out and corrected, after a short period of time. There are a handful of pedantic and extremely knowledgeable folks around these parts who are quick to point out better ways to do things. The rest of us point out other ways to do things, sometimes, in the guise of Perl golf or exploring weird tricks.
If new posters have the expectation that they'll get a good answer within 12 to 18 hours, I think they'll do okay. (If they grab the first answer, they may be in for a bit of a shock -- but on the whole, most of the answers here are good.)