I imagine it might be a negative emotional experience for a theist to see theism described as "the maddest thing you can believe without being considered mad.". There's being polite and there's being constrained in what you are able to discuss for fear that it might be construed as offensive by someone. I think the majority of the discussion here strikes a good balance, certainly better than the average for an Internet forum (admittedly a pretty low bar). Any individual might suffer a negative emotional response to certain specific posts that address topics that are 'hot button' issues for them but I would hope that if the general character of the discussions remains high we could all be thick-skinned enough to suffer the occasional slight.
I would suggest that a good rule of thumb for everyone would be to attempt to apply the most generous interpretation to language that could be considered offensive rather than the most negative. If someone says something that could be interpreted as describing you as a pervert and a chronic loser without any clear intention to actually describe you that way, perhaps it would be best to give them the benefit of the doubt.
Followup to Stuck in the middle with Bruce:
Bruce is a description of masochistic personality disorder. Bruce's dysfunctional behavior may or may not be related to sexual masochism [safe for work], which is demonized by most people in America. Yet there are ordinary, socially-accepted behaviors that seem partly masochistic to me:
Question 1: Can you list more?
Question 2: Doubtless some of the behaviors I listed have completely different explanations, some of which might not involve masochism at all. Which do you think involve enjoying pain? Can you cluster them by causal mechanism?
Question 3: When we find ourselves acting masochistically, should we try to "correct" it? Or is it part of a healthy human's nature? If so, what's the evolutionary-psych explanation? (I was surprised not to find any evo-psych explanations for masochism on the web; or even any general theory of masochism that tried to unite two different behaviors. All I found were the ideas that sexual masochism is caused by bad childhood models of love, and that masochistic personality is caused by other, unspecified bad experiences. No suggestion that masochism is part of our normal pleasure mechanism.)
Some hypotheses:
My guess is that, if it's a side-effect (e.g., 3) or a non-causal association (4), it's okay to eliminate masochism. Otherwise, that could be risky.
These all lead up to Question 4, which is a fun-theory question: Would purging ourselves of masochism make life less fun?
ADDED: Question 5: Can we train ourselves not to be Bruce without damaging our enjoyment of these other things?