Addressing the most stupid of opposition's arguments is not an enlightened way of discussion, but it's still way better than manufacturing and spreading widely false statistics.
You seem to be confused. Both of the things you mentioned are examples of "playing dirty".
If the other side played equally dirty, we would see articles like: "Did you know that 95% of violent crimes are committed by Social Justice Warriors?" or "Woman is most likely to get raped at the feminist meeting (therefore, ladies, you should avoid those meetings, and preferably try to ban them at your campus)".
But this is a very stupid way to play dirty because it is transparent and can backfire. Making a public example of the other side's inarticulate idiots is extremely unlikely to backfire.
Just leaving a hint: Imagine how a successful support for a false statistics could be used to design an ironic revenge at the very person who supported it.]
Just a hint: If you are using consequentialist arguments against playing dirty, then you are open to playing dirty if you can be shown it works. I submit to you that you have a failure of imagination.
I hope this sufficiently illustrates that the belief that the other side already is fighting as dirty as they can, and you cannot give them ideas by fighting dirty yourself, is completely false.
Strategic mimicry is not one of my arguments. You seem to be arguing with someone else. Regardless, see the "consequentialist" point above.
Simple examples of playing dirty:
Someone links a URL but it is broken in an obvious way. If you truly interested in arguing for the sake of argument, you could fix the URL and go to their link. But you could also take the opportunity to complain that they are just wasting your time and aren't really serious.
Sometimes, there is a finite amount of time or space for your opponents to reply to you in. You can pick arguments whose articulation is economic, but whose rebuttal is not. This puts a huge volumetric burden on them such that they will be unlikely
Scott, known on LessWrong as Yvain, recently wrote a post complaining about an inaccurate rape statistic.
Arthur Chu, who is notable for winning money on Jeopardy recently, argued against Scott's stance that we should be honest in arguments in a comment thread on Jeff Kaufman's Facebook profile, which can be read here.
Scott just responded here, with a number of points relevant to the topic of rationalist communities.
I am interested in what LW thinks of this.
Obviously, at some point being polite in our arguments is silly. I'd be interested in people's opinions of how dire the real world consequences have to be before it's worthwhile debating dishonestly.