Why would you even ask on IRC? And even more importantly why would you answer on IRC?

I mean as a means of getting help it's usable only for questions that take one or two sentences to ask and at most one sentence to answer. There it might ... if the right people happen to waste their time there and see the question fly by ... work, but anything that requires more info is ... bound to be frustrating for everyone involved. Someone types sentences as quick as he/she can ... without putting much thought into them, trying to explain, people randomly respond, comment or leave ...

Writing an email or a forum post gives the poster the time and space to formulate their question, format their post and ... the perceived "permanency" of the post helps to force at least some to put some effort into what they make public. With IRC you just start typing.

Discussing something with people you know (even if just online) is a different thing, but I know for sure I would not be able to stand the programming newbies (there is a difference between someone new to a particular language and someone new to programming in general) asking without know what is it they actually want as soon as it occurs to them that theres something that's not immediately clear. Without spending a few cycles of their own central processing unit on the problem first.