Oh cool they even have a word for what people would actually use this for.
Fallacy-dropping
“”What we have here is a blatant example of argument by assertion (
http://rationalwiki.org/wiki/Argument_by_assertion). It's therefore clear your mother was a whore, and you flunked out of elementary school.
—Colonel Custer[10]
It is not acceptable to merely state that one's opponent is using a fallacy (as above). One must explain how the opponent's argument is fallacious (eg, they claim that you are a shill), why it is wrong (there's no evidence that you are a paid government disinformation agent), and what that means for their argument (if you're not a shill, then your arguments can't be hand waved away) [11].
This need not be a drawn-out paragraph. Even "your ad hominem is irrelevant to my argument, so my argument stands" is sufficient.
Otherwise, one runs into the risk of fallacy dropping -- claiming someone's argument is wrong without bothering to explain why -- which comes dangerously close to ad hominem. (It's equivalent to shouting "your logic is bad!" and claiming victory.)
That's what I imagine the majority would be just copy and pasting words from this page as to why someone is wrong without actually understanding them.