(5) Quoted-readable/Mnemonic
Your proposal says...
Note that we only have to introduce extra quoting because of the character
set only arise if we use Quoted-Readable, ISO-2022 and ISO-10646-AUC.
I don't understand the problem in this situation with Mnemonic.
Indeed, mnemonic, since it is based on the glyphs of 10646 (and is a
superset of them) but not the structure of 10646, is the only proposal
on the table that gives us the properties of a universal character set
(e.g., different languages in different headers but within the context
of your proposal) without anticipating the approval of an International
Standard in a particular form. This, of course, assumes that the Asian
characters can be worked out in a reasonable fashion.
Well, mnemonic needs extra quoting. Mnemonic uses " and ( and )
all of which need quoting. About CJK I would rather use their
established ways of encoding them e.g. JIS encoding.
ISO 2022 raises several additional problems, arising primary because
it is not a character set but a collection of separable rules. If we
can avoid providing for it in headers, we can avoid replaying all of the
arguments about it that ran through the list in the (northern
hemisphere) spring.
I do not think CJK would like that.
I forgot the arguments from the beginnning of this (Gregorian) year.
I see the same second encoding princible being needed for
2022 schemes as for mnemonic.
Keld