The declension of the noun slua in PUL's works may reflect the influence of editors of his works, but a thorough word search shows the precise declension he uses is this:

singular: N: an tsluagh, G: an tslóigh, D: don tsluagh
plural: N: na slóighte/na sluaighte, G: na slógh, D: dos na sluaightibh

These are the actual forms used. Note the nominative plural found in his works is either slóighte or sluaighte (as in the 4 gospels -but this may reflect the hand of Gearóid Ó Nualláin who issued the nihil obstat).

Note that sluagh is normally feminine, but in the genitive singular, he regular uses "an tslóigh", as in "ar imeall an tslóigh", as if it is masculine in the genitive singular...

I notice that IWM has the pronunciation /sluə/ for the singular, and /sluətʹi/ for the plural, so there is little sign of a /slo:tʹi/ pronunciation.

Would people agree this word has /uə/ throughout the declension in pronunciation, and that the use of ó is probably some way of spelling the genitive singular and plural differently, but not pronounced that way?

quote:

Would people agree this word has /uə/ throughout the declension in pronunciation, and that the use of ó is probably some way of spelling the genitive singular and plural differently, but not pronounced that way?

Well, "slua" isn't the only word where /uə/ alternates with /o:/. In "nua", "nuacht" and "cnuasach" one normally hears /o:/ (or /u:/ alternatively in the case of "nua" /nu:/). This doesn't appear to be unique to Munster. We find Ballinasloe /o:/ in the English for Béal Átha na Sluaighe, Co Galway.

Yes, it is possible that /uə/ becomes compressed to /o:/ without native speakers really realising it.

It wouldn't make sense for slua to become masculine in the genitive.

I woke up this morning and for no reason at all, I was think about "ar imeall an tslóigh". It seems this is "ar imeall den ('en) tslua" - not genitive at all...

This business of writing "den" as "an" can get confusing.

Why not? Talamh and geimhreadh are two words which change gender in the genitive and there are others.