And looking back on the posters comment history, I would tend to agree. There is tons of absolutes, argumentation and quite a lack of tact.

Maybe I'm similar, but I can say that based on comments I've seen here I'd be far more likely to email jemfinch back than up_and_up.

I think it really depends on the company you are hiring for. At my present one, personality is absolutely as important as skill, so if you sound like a pretentious snob we probably won't be interested in you. At my last company (a fortune 500), if you sounded like the OP, we definitely wouldn't get back to you.

I'm interested in which particular comments you think demonstrate a lack of tact, and how you would improve them to be more tactful, if you have the time.

This one. The tactful thing would be to first accept the possibility you may at times come off as a bit conceited before asking for evidence and advice.