I hadn't commented on this to Nathaniel or Ned, previously, but I think that
the /alternative option is one of the more clever ideas in XXXX. It might
not prove useful, but is at least a good idea, for the reasons that Nathaniel
outlines. And there already is precedent for the idea.
At a minimum, it is worth noting that we already use the idea for publishing
some RFCs. There is a postscript version and an ascii one. XXXX gives
a mechanism for sending them together, and indicating that they are
'really' the same thing.