Is the "f" meant to be pronounced like that? It's been a long time since I did an Modh Coinníollach but I think in school we were taught that it should be pronounced more like a "h" (so like rach-haw, in this case)
I've never heard any dialect that pronounced the "f", though some in Munster apparently do.
The 'f' in '-f(e)á' is pronounced /f/ in (parts of) Munster.
However, the Connacht, Ulster & C.O. 'ch' of rachaidh (and deachaidh) is 'gh' in Munster, so it would be raghfá.
I was honestly unaware of that. I thought it was just "raghá". Thanks!
It's also why I stick to Rachfadh tú