What to do if an audience member refuses to let you answer their question? I was reading this question about famous people asking rude questions in talks, and it reminded me of a situation which happened at the end of my academic career. I would really like some advice on how I should have handled it.

I was giving a short talk at a conference and at the end the session chair asked for questions or comments. An eminent Belgian professor said "I really think you should look at X from 197y" and, since I had looked at X, I began to reply, and then the professor interrupted my reply with 


  "That wasn't a question. That was a comment."


I was speechless. This is Treppenwitz as it was several years ago, but what would have been a good comeback?
The question's title does not reveal the status of the obstructionist questioner, and this status matters enormously. Lower-status people behaving this way could not "get away with it". High-status people often can.

Given all the implicit primate-interaction and other presumption in anyone's behaving like that, in particular denying response, this should be treated like bad drivers on the highway, specifically, potentially more reactive than the indifferent bad weather or bad luck of various sorts. Namely, any substantial response, especially any expression of annoyance or umbrage, will incur a cost that makes whatever satisfaction one had hoped-for too expensive.

Instead, a dumb-happy-innocent smile and "thanks for your comment... then", to avoid engagement, is wise.

Sure, this amounts to a sort of impersonal bullying, but you yourself could not likely change the outcome. It'd require the intervention of someone of comparable status, blah-blah-blah.

So, in summary, no, such "comments" are not productive, are status-reiterating, ... and do create a generally stifling status-conscious atmosphere. Not that most human scenarios aren't status-conscious... :)