If this were implemented as I envision, then you wouldn't have to use the markdown methodology, you could just use the monastic style. AFAICT, Markdown parsing ignores something that's just in square brackets, so it would leave [radiantmatrix] and [cpan://strict] type links intact, to be processed by the monastic style. Only if it sees a string matching [.+](.+) (or, incidently, [.+][\d+] does it bother to process it.
Again, what I proposed is an implementation that no one would notice if they just used the current monastic style of markup.
After considering a couple of the comments here, I realize that some of the auto-formatting things would have to either be more intelligent or controlled through some sort of preference.
As for intelligence, it would be easy enough to turn specific Markdown items off when it makes sense: two line breaks followed immediately by container-type HTML tags would *not* be parsed as a new Markdown paragraph. If it sees italics, emphasis, bold, strong tags, assume all asterisks are literal. Use literal asterisks if it sees something like "great idea*" without a matching /\*\w/ somewhere before it in the paragraph. Etc. Most of this would be trivial, the rest would be mostly easy (though I'm sure there would be a few difficulties).
As for the option, I'd place a per-post checkbox for 'use Markdown syntax'; checking it would resolve conflicts between monastic markup and Markdown in favor of Markdown. When unchecked, all Markdown would be ignored. The default state of this checkbox would be controlled in user preferences.
I also don't like excessive autoformatting of text. I do like making some interpolation available so that I can concentrate on my content, and not whether or not I've remembered to break my paragraphs or wrap quotations of other people in blockquote tags (Markdown lets you prepend the paragraph with a single '> ' to deal with it.
I also feel bad for new posters that don't understand why all of their paragraph breaks (in the form of a double newline) disappear when they post, and they get chastised for it. Giving them an option that automatically deals with simple things like that is, I think, valuable.
Does any of that make you more comfortable with the idea?
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