Comment by grey-area

Frankly, I don't think what Grubber says matters here, and I see why he wouldn't want to engage all the trolls who are enraged by his inaction. Markdown works for him and he prefers it simple if somewhat vague/buggy, if you need something different, build it.

If someone wants to write a spec, a better parser or a better markdown full stop, there is absolutely nothing to stop them. The problem is, people would rather bitch about why no one else is doing anything and complain about gruber than actually do the hard work necessary. Do the work first, then look to gruber for canonization if you must, though by that point his views on the matter would be irrelevant.