By trying not to offend, you're also not informing someone of what is wrong. I've had you correct one of my posts and found it useful since it helped explain something which I clearly didn't understand. It would have been much less useful, not to mention more offensive (and I really shouldn't use the word "more" there, since the post wasn't offensive at all), if you had simply said something like "that's wrong" without giving an explanation why. Personally I'd rather have you reply to one of my posts with "Hey dumbass, that's the stupidest thing I've ever seen, you should have done ..." than something like "That's not right, reply if you don't know what's wrong with it" or "running with scissors" or "sticking paperclip in socket" or "watch out, that's poison ivy"