Of all the theories being advanced for Ireland's under-performance at the Rugby World Cup, it seems particularly unfair to blame Phil Coulter, writes Frank McNally.
Nevertheless, the argument has gained ground over the past fortnight that the debacles against Namibia and Georgia began with the singing of a politically correct anthem that fills nobody on the team with pride.
This is harsh. Ireland's Call was and remains an honest attempt to solve a real problem: the fact that Amhrán na bhFiann does not represent the whole island. It was also written - or so I suspect - to suit the limited vocal register of the typical rugby supporter. And as a song to unify Ireland's two communities, it has succeeded well, if only because music-loving Catholics and Protestants seem to hate it equally.
But the theory that a return to the martial sentiments of the Soldiers' Song would produce more passionate performances is simplistic. True, our opposition in tomorrow's crunch game will gird their loins with an anthem that warns French people about foreign enemies coming to "cut their throats", and urges a pre-emptive strike involving the use of the invaders' blood in a rural irrigation scheme.
Even so, it seems to me that the outstanding quality of La Marseillaise is its irresistibly catchy tune. I for one will be humming along as usual tomorrow night. And I suspect that, with a little effort, teams playing France could use the song as a motivational tool. In fact, like most anthems - including ours - the French one has something in common with Italian opera. It's probably easier to enjoy if you don't understand the ridiculous lyrics.
An even more inspiring song is Land of my Fathers, surely the loveliest national anthem in the Six Nations Championship. It never fails to stir the emotions when you hear it sung in Cardiff by a choir of fifty or sixty thousand home supporters.
Which is why I have a theory to explain Ireland's uncannily good record in Wales over the past quarter of a century. While the Welsh are much better singers than we are, I suspect that our love of music is greater; so that the massed singing of Land of my Fathers inspires our players more than it does theirs. I could be wrong.
There is no danger of the Australian national anthem inspiring the opposition. But it can hardly inspire the home team either. Musically and lyrically, Advance Australia Fair is as stimulating as weak tea, despite having a range that only a trained soprano could sing properly. The theme tune from Neighbours would be more likely to rouse passion. And yet this has not stopped Australia winning two world cups, one more than New Zealand.
Speaking of which, I used to think that the Kiwis had devised - in the form of the famous Haka - the ultimate method of motivating their players at the expense of the opposition. But far from being the warlike ritual it resembles, the best-known version of the Haka in fact a work of satire.
Apparently it commemorates a cannibal chief who escaped becoming his enemies' lunch by hiding in a hole, over which the wife of a friend squatted while pretending to urinate. Reluctant to intrude on her privacy, the hunting party passed on, and the chief emerged to fight another day. But his undignified escape was immortalised at his expense, via a Haka whose lyrics make reference to his "hairy" saviour.
Those who believe in the power of anthems will point to the Georgian players who nearly beat Ireland last week, and who did appear to be pumped up beforehand by singing their national song. But then again, since the fall of the Soviet Union, Georgia has had more different anthems than Brian O'Driscoll had hairstyles. I suspect the passion of their performance had more to do with economic imperatives than with music.
Besides which, the allegedly inspirational powers of Amhrán na bhFiann have always escaped me. Many times I have heard it sung where you would think it matters most: at GAA games in Ulster. And while treated with great reverence there, it is always rendered in a barely audible murmur, the way Catholics sing hymns in churches with no choir. The predominant emotion, it seems, is a fear of being heard by the person beside you.
By contrast, the most emotional sporting occasion I ever witnessed was the night in London in 1985 when Barry McGuigan won his world boxing title. There could be no question of either the Soldier's Song or God Save the Queen being played beforehand. McGuigan drew support from both parts of Ireland, and his career had skilfully straddled the divide.
National flags were banned ringside. The only colours used were blue-and-white, which represented Monaghan, or the United Nations, or whatever you were having yourself. Political anthems were equally avoided. Instead, McGuigan's father sang Danny Boy, and there wasn't a dry eye in the house.
A sports psychologist would struggle to explain how an old air with lyrics written by an English lawyer who never set foot in Ireland could become such a potent motivational weapon. Especially since, like McGuigan's career, the song is a masterpiece of ambiguity. The singer could be a lover, a mother, or even a father. And we are never told where Danny is off to. War? America? The pub? All we know is that the singer imagines him or herself dead and dreams of the day when, first, Danny will visit the grave and, later, join the singer in it. It was an unusual sentiment with which to fire up a professional athlete, and I often wondered what Eusebio Pedroza, the veteran champion who was about to surrender his title, thought. But it seemed to work. Whether he knew it or not, by the time the fight started, Pedroza was already about three rounds down.