Re: objections to webmention

While I agree with Melvin's design aesthetics, I acknowledge that's what
they are.  There's no _functional_ problem with the current spec, and while
JSON-LD and URIs seem like a good practice, there's nothing written in
stone that says Thou Must Use URIs.

I disagree however that it's a general purpose messaging framework. It's
explicitly (per the one sentence introduction):
  "[...] a Webmention is a notification that one URL links to another."


Basing any understanding of webmention on the non-normative extensions
referenced seems like a trap to be avoided.  I (personally) would simply
remove Appendix B and focus on the actual value of the main specification.
Extensibility without namespaces at web scale is just impossible, and may
be leading to some of the confusion and design questions.

Rob