Have you ever had someone say that to you? Have you ever said that to someone? Ever noticed how when someone says, "No offense," they are just letting you know that they are going to be offensive to you, and you should just be nice about accpeting it?
How about if instead we all quit saying, "No offense," when we know darn good and well that we are going to be offensive. Maybe we're mad about something. Maybe we have been treated poorly by the preson in question. Maybe we are being defensive because we have been called out. Whatever the case may be, "No offense," is an almost certain prelude to something offensive.
So how about this: quit saying no offense. We aren't really fooling anyone. We all know something bad is coming. So instead of trying to hide the insult behind something else, how about just saying it? Why lead in with, "No offense," when you can just tell the person how you feel. Let's face it, we all offend people, whether we mean to or not. I know that I for one would prefer someone to say to me, "Hey, I think your teaching sucks, so I'm dropping your class." Yes, that would hurt for a bit, but at least it is honest. I could say the same for my writing. I would rather someone say honestly that he or she doesn't like my writing than say my writing is good and then proceed to never again read anything I have written.
"No offense," seems a bit dissembling at best. I talked about being earnest in a previous post, and I really think we should all strive for that. As for me, I will do my best to remove, "No offense," from my vocabulary.