I think if anyone here feels they have to stand up in the middle of a presentation (of any kind) and insultingly disrupt the person's delivery, they should contact Barack Obama........ he is looking for people like you.
My only exception is if you are the Pastor and have a guest speaking, you can and should stop them if they get into the ditch...
I had a guy try to date set "the rapture" and invited the people in our fellowship to join him...he probably felt like a rapture happened because he was out of the door in the twinkling of an eye...