Very good point. Best thing you can do on SO is starting a chat with the user I think, or sometimes you can give a 'teach a man how to fish'-style answer where

Very good point. Best thing you can do on SO is starting a chat with the user I think, or sometimes you can give a 'teach a man how to fish'-style answer where you don't just give a code-only answer (i.e. how), or maybe don't even give a complete direct answer at all, but explain the bigger picture (i.e. why). Problem with the latter approach is that if the OP doesn't leave any comment you don't really know if it helped at all, whereas chat is more direct. But if you do get a 'well now I learned something' type of comment there's a good chance it actually helped the OP becoming more knowledgeable.