Rivka, you overestimate the differences between the Tiberian and the Babylon
Masoretes.
To relate the current pronunciation to obscure etymology is doubtful at best.
The environmental explanation is actual, not a mnemonic rule. A single vowel
[a], kamatz, is pronounced as short [o] in closed unstressed syllables. Such
environmental peculiarities abound in many languages. In the carefully
chanted Hebrew of the Masoretes, kamatz is [a]. Environmental pronunciation
of kamatz as [o] is a colloquial phenomenon. How, in your opinion, such
environmental variation "is not consistent with language development"? Long
[a] shortens to short [o]. What's the inconsistency?
I'm not sure what exceptions you're talking about. You're welcome to point
them out. Most certainly, they are not related to long-forgotten etymology.
Would you suggest several examples of the "etymological basis of vowels," of
holam becoming kamatz katan?
Vadim Cherny
We need to remember that the Masoretic pronunciation (which pronounced both
kamatz vowels identically) was not the only Hebrew pronunciation at the time.
At the same time that the Masoretes vocalized the Tanakh per their
pronunciation (I suppose, the pronunciation that was used in the northern
part of the Land of Israel) two other vowel systems have developed, based on
pronunciations that were different from that of the Masoretes. The one
developed in the center part of the Land of Israel (called the Yisraeli
(formerly "Palestinian") vowel system) and the Babylonian vowel system. Both
of these systems had not only different vowel symbols but were actually
different pronunciations.
The Sephardi pronunciation, which retained the etymological origin of the
two Kamatz vowels is based on the Yisraeli pronunciation, even though all
accepted the Masoretic vowel signs. This is exactly why we have the
"problem" of one symbols for two distinct vowels. So the etymological basis
for kamatz katan was not forgotten -- it was kept intact by Sepharadim in
their Hebrew pronunciation, and have later become the basis of these vowels
in modern Hebrew.
The "environmental" explanation is merely a "technical" framework; it's a
useful rule, but it doesn't explain why we have in Sephardi and Israeli
Hebrew two different vowels with the same symbol; it doesn't address
"exceptions" (which are not really exceptions if one looks at the word
etymology rather that strict adherence to rules); and is not consistent with
language development.
I find it difficult to accept your explanation of kamatz katan as a
"vulgar" presentation of certain kmatzim since the fact (i.e. the
etymological basis of vowels) is so clearly present in the Sephardi
pronunciation. It is well known that the Sepharadim kept throughout the
generations the differentiation between the two vowels, even though they used
the same symbol for both, because they accepted the Masoretic nikkud.