I just checked and it seems my library has the Doyle. I've been leafing through it and it seems pretty sound--not as comprehensive overall in its coverage as Ó Siadhail's Modern Irish (particularly regarding phonology and dialectal variation) but with a robust section on syntax. (I'm particularly intrigued by his suggestion that Irish is actually default SVO on the basis of its small clauses with surface VSO being the result of fronting the finite verb--have to read more on that.) I'll have to make some time to sit down and read through the whole thing.
"Richmond is a real scholar; Owen just learns languages because he can't bear not to know what other people are saying."--Margaret Lattimore on her two sons