It doesn't help that even the most offhand posting is generally treated as if it was an academic paper and ~~reviewed~~ skewered accordingly :-p.

I agree. There are definitely times for unfiltered criticism, but most people require a feeling of security to be their most creative.

Agreed. This is, for me, one of the main advantages of posting on tumblr. You still get the feedback you want from clever people and criticism, but that criticism doesn't feel quite as bad as it would here, because everyone realizes that tumblr is a good space to test and try out ideas. Less Wrong feels, to me, more like a place where you share more solidified ideas (with the Open Thread as a possible exception).