I really don't know what part of what you said was tactless.
Blunt and rude perhaps but tactless? You sat through a lecture for a few minutes, interrupted said lecture and had a go at the lecturer for teaching something as part of the course material. So you interrupted your entire class's teaching with something you probably would have been given time to share when there's a natural pause in the lecture or at the end when a lecturer asks if there are any questions. Also you sounded really rude too or does being polite not cut it when you're "being passionate".

I probably sound quite rude here and I generally enjoy your posts but this one isn't very good. If I was there and didn't know you I might just have muttered, 'twat' under my breath.
(Smysha Tra la la!, Sun 6 Nov 2011, 0:32, Reply)