Prof. Abelson wanted to hammer home the point porn was a problem on the internet back in 1998 and thought putting up a porn site for the first slide of a lecture would make his point.
Was his flashing the room like that a free speech issue - or a thoughtless dickhead issue?
Independent of his legal "right" to conduct a class in that manner - it's basically kind of asinine to assume your students need to have their buttons expressly pushed in order to appreciate the basically obvious point he felt he needed to make. Or that if people object his resorting to such a stunt - that means they're "offended" by it.
Prof. Abelson wanted to hammer home the point porn was a problem on the internet back in 1998 and thought putting up a porn site for the first slide of a lecture would make his point.
It was pretty shocking when it happened.