more on this temperament tangent

[A440A@AOL.COM]

Greetings, 
Tom Sivak writes: 
<<The thought that composers compose in temperaments is ludicrous. >>

   Ah,  now this is interesting. Of course, I also think it is totally wrong, 
but we should both offer logic to support.  
   Why do we find no compositions of Gregorian chant that use all 12 notes?  
Why, before Walter of Odington's writing in the 14th century, does it seem 
that thirds were not used in composition?  Could it be that the 81/64 
interval that resulted from the use of pure fifths might have been too harsh, 
and was regarded as a discord, thus making it unfit for use?  I think so, and 
the evidence seems to support that.  Or would composers of the time just 'not 
think of them'?  Illogical, I say. 
   If composers didn't obey any temperament influences,  then how do we 
explain the renaissance and mannerist keyboard music that was composed in the 
meantone era?  If the restrictions formed by the temperament of the time are 
not evident in that music, then we must assume that the composers just never 
wanted to play an Ab, or C#, etc.  That is stretching some pretty thin logic. 
Would you ascribe the lack of modulation, in virtually ALL keyboard music 
before 1650 to just coincidence? I consider this so unlikely as to be 
impossible. 
   Slightly along the same lines,  we would have to wonder why Vincentino 
would have gone to the trouble of having his archecembalo built, (two 
keyboards tuned a comma apart in order to create, effectively, a 19TET 
capacity).  Was he not attempting to create an intonational capacity to suit 
his idea of harmony?  Isn't this evidence of a composer aware of temperament?
   Why did Bach compose his preludes the way he did?  The C and C# appear to 
make use of the particular resources of WT's respective keys, and if 
cross-transposed to each others', totally lose their charcters and musical 
balance. This is not true if the transposing is done in ET, but are you 
prepared to say that Bach was using ET in 1722?  That can of worms has 
already been left out in the sun and is now dry and crunchy... 
    The later Romantic composers seem, (to me, although I know some die-hard, 
hard-core temper-heads will disagree, and they DO have some healthy 
evidence), to rely on washes of chords, which I hear working best when the 
"color" doesn't change.  This, to me, seems to indicate they were working 
with ET, or something so close to it that the differences are academic. 
    That composers were not influenced by the tuning of their times is as 
believable as the idea that they are not influenced by the qualities of their 
instruments. The latter can be judged by use of artifacts but the former must 
rely on an interpretation of the literature.  To this end,  I would like to 
hear Tom's evidence that temperament didn't influence composition.  
Regards, 
Ed Foote