Interesting work! I've put together some thoughts on how markup/down/left might be used as slightly lower level tools to address some of these issues. It was

Interesting work! I've put together some thoughts on how markup/down/left might be used as slightly lower level tools to address some of these issues. It was great reading these because a lot of the problems simply hadn't come to mind when I was first thinking about this. I want to dwell on it for a little bit (day or so) and then I'll send you an email.