I can't see anything immediately wrong with having an open thread where people can declare generalized Crocker's Rules and receive feedback. I'd encourage the 'actually declaring Crocker's rules' bit to lessen the risk that people will become offended (since we do happen to be primates.)
Talking about a norm in relation to this seems like a bit meta-off-the-deep-end. People can already declare Crocker's Rules if they want, and I don't really think we have a problem with a lack of critique in general.
Oh, and I'd greatly appreciate feedback. :D
Crocker's Rules!
Most people need feedback in many areas. Most people can give feedback in many areas. But for some reason I don't see a lot of actual honest feedback happening, neither in my personal life, nor at work, nor here on LW. This looks like some sort of market failure, or perhaps a bug in society.
Would we benefit from a norm that encouraged asking for feedback or critique in any area, perhaps using open threads set up specially for that? I think we would. What do you think?