Listening for Stasis

Up close, music is anything but stasis.  This morning I heard an a cappella choir rehearsing.  Suddenly there was a perfectly tuned, fully resonant F major harmony.  Later, when they sang the same work in the context of the service, that "same" harmony was nowhere to be found.  Vocal intonation is not in the least static.

Preparing to perform the Schubert Op. 122 E-flat Piano Sonata I was reviewing some of the G-flat passages in the last movement.  It struck me that their fragility was very like that of the vocally fragile tuning I had just heard.  G-flat is a marvelously stable key on the piano when it is the home territory.  But when it appears in the middle of an E-flat movement it virtually "undoes" the stability of G, so essential to the tonal definition of E-flat major, and it changes E-flat itself by the introduction of D-flat rather than D-natural.

It could be that my ear is particularly sensitive to such changes:  I have spent my entire musical life singing as well as playing the piano, and remain deeply involved with a cappella tuning.  When the overtones of a given piano pitch are tampered with in the course of a composition I can taste the whole environment going sour, as it were--tilting in search of the stability I have learned to crave in the course of the composition.

I know from having performed chamber music with many different instruments and personalities that this structural instability is not acceptable to some musicians: they will simply not allow the composer to effect such a significant structural upheaval.

Is it a result of recording techniques that correct every deviation from the strictly correct, even when it is musically wrong to do so?