If the base, for headers, is mandated to be 7-bit and if we do
not envision changing the standard to any other base, then why
do we need to provide an explicit label for that in the quoting
The encoded word has the encoding as one of its 3 required parts. If
you want to use the encoded word to explicitly identify a 7 bit
character set, say iso-2022-jp, with the current specification you
would be required to specify one of "b"inary or "q"oted printable when
neither is necessary.
This brings up a question, Eric, is the "q" encoding excessively
burdensome for none ascii text? I confess that I have not studied the
2022-jp specification yet, but if the set of octets is passable as
ascii they would generally not require quoting. The incremental
processing required to un-do the quoting seems to be minimal beyond
that required to parse the encoded word.