Dave Crocker writes:
Let me stress a point that Nathaniel made in a note, earlier
today (and probably overlapping your note in time): Framing
-- and quoting is a kind of framing -- is MUCH more robust when the
start-of-frame and the end-of-frame are different. Serious
syncrhonization errors can occur, otherwise.
One way of avoiding such problems is to make the special rendering
of text always end at an end of line. This is no serious restriction,
since it is usually used for single words or just a few words in
sucession.
The problem is to have a format for special rendering which looks
reasonably nice when read by users who do not have support for
the special rendering. "***" "###" and "_" are acceptable from
that viewpoint. Anything more complex would look even more un-neat
to users without support for the special rendering.