And Dollhouse in general: is it attacking sexualised abuse of women and wider dehumanisation for commercial entertainment, or wallowing in it while pretending to attack it?

Announce that Dollhouse is the best thing Joss Whedon's ever made. Bonus points if you're in the company of Browncoats.
Speaking of Browncoats, go just about anywhere science-fiction TV is discussed (including this wiki) and suggest that Firefly is anything other than perfect and without flaw.
Speaking of Joss Whedon in general, criticise his reputation as a feminist or his depiction of women. Then enter your nuclear fallout shelter buried deep within a mountain and bunker down. Oh, you don't have one of these? Poor you...
Depends on the forum. In some parts nowadays, praising Whedon as a feminist will get you dogpiled by people explaining in exhaustive detail what a hypocritical misogynist he is.

Just about anywhere, and certainly in this wiki, suggest that Firefly is not perfect and without flaw.
Bring up the fact that the series is about a blended American-Chinese culture, yet no Asian actors were cast in any of the lead roles, and only one was given any lines even in minor roles. The consensus is that it was an accidental oversight, but whether it was because of Joss being occupied with trying to keep the show afloat, or whether all the Chinese stuff was just window-dressing is heavily contested.
Or mention that Kaylee is never anything but a useless, helpless little Damsel in Distress unless engines are involved.

Throw a dart on a Buffy the Vampire Slayer forum. You'll still find arguments. Especially of the shipping war variety.

The words "Seeing Red" work really well.
And while you're at it, casually mention you hate Angel/Buffy, Spike/Buffy and Angel/Cordelia.
For that matter, mention that you actually liked Buffy/Riley. Bonus points for saying it was better than Buffy/Angel and Buffy/Spike, which will draw in more incensed fans and bring in another argument. Even saying you liked Riley himself, or that he's decent, is a seriously bad idea.
Never let anyone know you ship, or are at least okay with, Xander/Dawn unless you want to be called a paedophile or lectured on how it's basically incest.
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