I think if you said to me “How uneducated are you?”, it wouldn’t really matter what the context was. I would just see it as a rude, unnecessary, remark. Similarly, some of the other examples that @asnac has given. It is sometimes hard to be reasonable and polite towards people, I know, but context can’t always be used as a reason to say some things. I think I have probably had about 4 ‘spats’ with people on this site, over a period of around 12 years, but I don’t think I have been regularly, overtly, rude as, at that point you have lost the argument. As far as the ‘ignore’ button is concerned, I haven’t used this. However, there is one poster who I have recently decided to ignore by reading past his posts, or more specifically, not responding to his posts. I think this is a better way of doing, personally. I would imagine that if you clicked ‘ignore’ on too many people, you would perhaps lose the fluency of some threads in the process.