so. Did some research. this "markdown" was released in 2004. and then dumped by its creator, (the same year), and is only maintained by a small core of fans. there is no standardisation of it.
So who knows what "flavour" we have and how it's implemented (inflicted on us)
just cos some think it's "trendy"
telling is, outside of programming sites it's hardly used. where as, standard controls are used on mainstream forums and forum software... rather telling.

and now we're stuck with it.