Yes, that is what I mean by "gliding". However, in Russian language, it is not necessary to add a Ь in front if it. Isolated E glides already. Ь or Ъ regulate the prononciation of the preceding consonant, rather than E itself.
I seriously doubt that similar differences don't exist in other Slavic languages, including Russian and Bulgarian
They probably existed at some point, just like they existed in Greek. But today, in Russia and in Bulgaria people lengthen and shorten their (stressed) vowels, often in an exagerrated manner, to add emphasis and without regard to what word it is, like singers do in songs in any language. This does not add a sillable. Normally, all vowels are pronounced middle-length, for example, И is pronounced as a bit lengthened I in "big" or a bit shortened EE in "beef".
Thus победа is pronounced as побъеда in the western dialect but as побэда in the eastern. The word used to be spelled uniquely as побѣда, but today it is spelled побједа and победа.
I understand. In fact, when the orthography reform was instituted by the Soviets, it was pointed out that Ѣ is not exactly superfluous even in Russian. But the argument sort of died down, quite possible because like with everything during these wretched times, orthography was politicized as well. Ican easily imagine people beign sent to the Gulag for the Ѣ letter.
I did not know my grandmother, but I new my granddad's sister. She was born in 1898. One of the things that caused he to feel bitter even in her old age was the episode when she -- a bookkeeper -- submitted some report to the boss, something she knew was done well. The boss returned it with a red pencil across the front page: "I request that new orthography be used". She did not end up in jail, but that was among her grievances with the Soviet power that she would secretly tell me about, how they made her rewrite (or retype) the lengthy report that was perfectly comprehensible, in fact more comprehensible to the Russian reader, in the first place.
how is святость pronounced in Russian?
It is pronounced "svyatost", as written. When Я is not stressed, it is subject to the same phonetic reduction rules as any vowel, so "посвящение" would not sound differently than "посвещение".
Everybody does that, Alex. Even in English, i.e. "I am sooooo happy..." This doesn't mean different words don't have vowels of different correct length. For Russian and Bulgarian this is not an issue. For Serbian, which presents itself as (supposedly) a "phonetic" language, it does.
I understand. In fact, when the orthography reform was instituted by the Soviets, it was pointed out that Ѣ is not exactly superfluous even in Russian
Such as? What is the difference in Russian pronunciation between вести and вѣсти? In Serbian it is clear as a bell. The western pronunciation is identical to Russian; the eastern is вэсти. Clearly, ѣ would serve a useful orthographic function in Serbian, but where is the equivalent in Russian?
orthography was politicized as well
Pretty much the way Serbian Cyrillic was identified with Serbian nationalism and forced out during the communist regime. In the mid 1960's, for example, Serbian (but not Macedonian) Cyrillic typewriter production was stopped. When I was in Belgrade in 1986 to bury my mother I couldn;t find a single Serbian Cyrillic typewriter there. But I could easily obtain one in the US! The country was forcibly being "latinized" and good part of the problem with two alphabets today is the result of that. The fact that Cyrillic is the official (constitutional) alphabet seems to be ignored on a wide scale and politics still play a major role in the issue.
Violations of the Constitution in that regard can be found all over the place, from the courts to the very online office of the President! Many "European" Serbs opt for the Latin (Croatian) script because they firmly believe the foreigners will better understand Serbian! Others say that Cyrillic is a Babylonian type of alphabet that has outlived itself by a long shot.
In the Bosnian Parliament a fistfight erupted when a Serbian representative asked for the printer material to be in Cyrillic (constitutionally guaranteed right). In Croatia, a petition has been circulated to obtain enough signatures that would allow local municipalities populated by at least 1/3 Serb population to display public signs in Serbian and in Cyrillic in addition to Croatian (which is exclusively written in the Roman characters).
So, I am very much familiar with the politics of orthography. Even as recently as 2000, some Serbian linguists launched the idea that the Latin script used (Croatian Latin alphabet) is "also" Serbian, i.e. "Serbian [sic] Latin alphabet."
It is pronounced "svyatost", as written
I guess it must be that "gliding" Я. I remember distinctly Father Arkady, who headed a sizable Russian orthodox congregation in a local OCA church pronouncing святий with a muted "e" that sounded very much like светий. :)