Bill Cutler writes:

>As far as publications are concerned, the ability to read music is a
>requirement essential only to those written by and for composers and
>musicologists

I don't quite agree.  I'm neither a composer nor a musicologist, but
I benefit when someone tells me how a piece might be put together. 
What you assume is that only composers and musicologists know how to
read music and therefore can be the only beneficiaries.  Also, some
of the greatest music critics for the general reading public were quite
well-trained without being musicians themselves.  Shaw, in particular,
prided himself on never using musical type for his articles (except to
make fun of the critics who did).  But I doubt that his criticism would
have had its force without his musical skill.  Samuel Butler, a writer
of as great polemical skill as Shaw and who also wrote on music, revealed
himself as a crank.  His judgments haven't survived; Shaw's have.

Steve Schwartz