No, no, people who cut off discussion like that are smug, cowardly jackasses who want to rub it in your face.
If you want a debate to end you either:
1.) Concede that you're wrong.
2.) STOP POSTING; THIS IS THE OPPOSITE OF DIFFICULT.
If the person is not reasonable after so many posts, any further posting is just to convince the audience and/or humiliating the opponent.
Other phrases:
"I have better things to do."
"Some of us have _______."
"Clearly we have no room for further debate.*"
Why are you telling me this with a post? Why? This isn't an "oh I was busy" situation as much as making sure everyone knows the other guy is wrong (for some reason) and then rage quitting the thread.
Not posting is less terrible as it isn't an "I'm right so there nyaa" post
*This happens after 3 posts when there has not been a single wall of quotes. Unless the participants are debating chessmasters who know the outcome after 3 moves, this is dumb. This happening a ways in is acceptable I guess.
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All this probably goes under my general dislike of the clever passive aggressive behavior that develops in "clean" forums.
Where this happens all the time.
Oh right, replace posts with minutes and everything still applies. Use context clues.