I just picked up on this thread. It has been several years, but way back when Thumb was first posting OWNED TEACHER on the asst. sex newsgoup he attached a authors comment on the last couple chapters that stated he was very ill. That the story was never fully completed I have always wondered about Thumb's health.
The work is a classic. I have always thought (if Thumb is no longer able) that it would be great if a competant author could finish this.