Kind of funny, I was just looking at adding similar functionality to an internal Chrome plugin I built because we struggle to get enough useful info in bug reports (being able to look at the HAR, in particular, is useful, but difficult to get users to do correctly).
Two questions -
1) Any way to customize which headers/cookies get scrubbed?
2) Is there a way to get something like the lower-level export you can get by going to chrome://net-export/?