The chatterbox is a different forum then a node. Shorter, usually less formal, more spontanious. Just as an IRC chat with a friend will differ from a paper or presentation, style changes between nodes and chatterbox.
Clearly, what some monks are concerned about is that offhand, non-verified, etc. comments are going to be taken down and potentially held against them in perpetuity. If you've got a reputation outside the site and your livelihood depends on it, that's potentially worrisome.
I think you're spot-on about the point of the chatterbox. As author of some of the posts you mention, I've found it a fertile ground for new ideas.
OTOH, if the *context* is clearly represented "Mind you, this was a chatterbox log and no opinion expressed herein should be taken as definitive of anyone's considered or even unconsidered opinion, the poster may have been just letting off steam or fooling around, as even Monks need to do occasionally", what's the sense in saying a person will be *misrepresented* by posting a chatterbox log?