Good question. I don't know how the gods feel about it, but I personally believe that an unrestrained proliferation of shortcut types is not in our best interest; and a request for one from a single user isn't, by itself, sufficient justification for it, precedents not withstanding.

we still have the [by://] shortcut

Yeah.... I would have cast my (moot) vote against that too, probably. (Although it sounds rather hypocritical of me to say that, since I wrote the patch which implemented the [by://] scheme...)