Well I have been on the giving and receiving end of the first two scenarios and I would have felt cheated if any of my very good University friends (they know who they are) had "done it for me" I definatly appreciated every minute of the long hours some of them would sit with me and take me though a problem that I just didn't get. On the other hand when giving help I did find it hard not to rip the keyboard out of peoples hands just to get the problem fixed.
in reply to When do you step in, and why?
At the other extreme of course I would have no problem tearing the keyboard out of their hands, and I very mutch doubt there would be any objection. There are times for learning and there are times to swallow your pride and get on with it. :-)
---If it doesn't fit use a bigger hammer