I personally like the idea of short tentative summaries. That way I have a few paragraphs so that I don't forget things, but I can change them at will if the characters start organically going their own way. Just in the last few times I've had characters who were supposed to be paired turn out to have no chemistry other than friendship, and another where I switched the personalities of two characters completely. So in that, I'm somewhat half-pantsing. I do most of the drafting in my head, which is probably a horrible habit, but one I have none the less, but it's never too constricting. I have to remove some scenes sometimes if a character goes too far (one draft had a character completely changing, for example) but most of them aren't too drastic.

This is an interesting argument for "pantsing." Pansting is so frowned upon in a lot of how-to books and such. I've rare seen much in defense of it other than "this is how I do it, screw the rules I have money!" sort of mentions.