The "right" pronunciation
In a comment thread on Mar Gavriel's blog the question of reclaiming ancestral traditions came up. I'd like to mention some issues and take as an example the question of pronunciation.
Maybe a reasonable compromise might be to go back to the most recent stage that makes sense and is legitimate, either as a whole or deciding each detail. What exactly your criteria are for "legitimacy" isn't easy. For example: If you accept the palestino-tiberian system (which, I think, all communities do today) and you're Ashkenazzi in your pronunciation, you distinguish pasech, chôlem and kometz.
Now, say if you're Dutch, that would be roughly [a] vs. [au] vs. [o]: hatTauro. The [au] clearly developed from an earlier [ou]. Do you consider this a legitimate change or development in minnek? After all, from the POV of phonology, it doesn't play a rôle if you say [au] or [ou] - you won't confuse words because of that. In fact, maybe it's even better from the POV of haloche, because [ou] is closer to [o], and if you slur it a bit or you don't hear well, [au] is more distinct.
But - [ou] is the older one: hatTouro. And it doesn't stop there. Probably it used to be [a] vs. closed [o] like in French or German vs. open [o] like in shawl. Should you go back to that? That's what the massoretes had in mind: hatToraw.
But - there were other massoretes, and I'm not sure the palestino-tiberian system we use today is compulsory. Sefardis and others use it in theory, but that they don't make a difference between pasech and kometz is a heritage of an earlier parallel system: hatTora.
Was the Redak's novel systemisation legitimate?
Up to some time between the 13th and 16th centuries ChE, we Ashkenazzim didn't distinguish between pasech and kometz either (hatTora)! Should we go back to that stage? Does this depend at all on the question if the change to a system that does distinguish came about through the "Babylonian renaissance", i. e. teachers from Mesopotamia where the system had been accepted at the time, like some scholars suggests, or because of inner-Yiddish, or even -German developments, as think others?
Not that it stops with the massoretes. It starts to get halochically and hashkofically precarious here: We have the normative massoretic tradition, but linguists tell us that at the time of the Tôre, it was all different. "She" and "he" in Hebrew would not be hi and hu, but hiwa and huwa, there wouldn't be a fricative pronunciation of the begad-kefas consonants, and these are only some harmless examples. All of this still doesn't scratch on the consonant letters of the Tôre. Should you go and accept that? Does the normative idea that there is an unbroken tradition since Sinai include the vowels?
Personally, going further "back" than the massoretes clearly doesn't seem right to me. Otherwise, I'm just not sure. Personal likes and dislikes, which I certainly have, must be secondary to the question what is right. Then again, if I say I can't adopt the pre-Ashkenazic pronunciation because it doesn't conform to the din, I'm actually saying my ancestors did it wrong for centuries - and they had a continuous tradition, as opposed to a conscious break like maybe the change from pre-A to A, and certainly the change from anything to Israeli Ivrit.
You bet before I go into publishing tefilles, I'll have a very close look at that and more than a casual talk with rabbonem.
(Update: Additional issues in the comment section.)