When I was in my mid-teens and studying for my GCSEs (late 80s) I went to see his show "Acting Shakespeare" in London. I was confused about a couple of things he'd referred to, so wrote and asked him to clarify. The guy took the time to write me a lovely letter, explaining the points he'd made, and also offered a load more advice regarding the play I was studying. He ended it by thanking me for my letter and wishing me the best of luck. Hardly the actions of someone who's "up their own arse"!
Personally I think he's a brilliant actor and always come across as a lovely bloke in all the interviews I've seen.