I think you make an excellent and valid point.

On the flip side, developing a spec---for something as popular and accessible as Markdown---out in the open is an extraordinarily difficult task. I think one can definitely make a case for it being the right thing to do (and I mean that in more than just the ethical sense), but I also think one can make a reasonable case for not wanting to travel down that road either. I think it can be so difficult that there would be a very real possibility that it would never get completed.

(I'm sincerely not trying to be combative. I know I'm not really addressing your point---that they didn't even provide a status update---but I just wanted to provide a tiny perspective on the other side of the coin.)