I had a look at your PR. My respect for your persistence is assured!
However, I wonder if such extreme minimal syntax is really the right approach for a wiki. @andi has already pointed out a difficulty with possible ambiguities.
Albert Einstein said: "Everything must be made as simple as possible. But not simpler." (Source seems to be somewhat dubious)
Maybe you should outsource this functionality to a plugin, because it is probably only desired by very few. Especially since it is already covered by an existing syntax.
- Michael Sy.