One big problem I have with "niceness" -- as you put it -- is that it involves an awful lot of framing and preparing any sort of topic for discussion, and that imposes a not inconsiderable additional burden of speaking and listening on the discussion's participants, while communicating very little. It is phatic speech emphasising sociability over information transfer.

I think that this problem is evident in the way that you express yourself on this blog. You often commence with several disclaimers, continue with constant qualifications, and conclude with apology and self-deprecation. You have to write those words, and we have to read them.

I wouldn't get hung up about it, as to a large extent it's a beneficial practice. You have tended to write about sensitive subjects of late, which deserve extra care. But perhaps it can be taken too far. It can make your arguments less compelling by clouding them in pusillanimousness, needlessly weakening the authority of what could perhaps be condensed to more striking propositions.

My challenge: write your next post on race / gender / class without any framing niceness. That would include avoiding any mention that you're not being nice for once, or any reference to this post.