Religion, politics and Irish comedy - three conversations likely to end in high dudgeon. Whatever about the incendiary nature of the first two, we all know of dinner parties ruined, promotions missed, friendships ended and marriages requiring third party intervention because someone declared a love of Mrs Brown's Boys.
While Irish lark The Stag will attract those whose default mode is goodwill and cinematic patriotism, it really has its work cut out to entice that fair old whack of the population who contend that they've witnessed far funnier on a stage, bus or train here than they ever have on a domestic screen, small or big. For them, a remake of Die Hard in Liberty Hall would be as likely to yield rewards as a story about six lads on a pre-nuptials ramblers' weekend in the West.
And if any such punters do manage to make it into the queue for The Stag, there won't be a Damascene conversion - but even the pathologically churlish should be able to admit that this film is not without its merits.
The groom-to-be in this case is Fionnán (O'Conor), one of those clingy and painfully enthusiastic types that Dublin has become a world leader in nurturing. He's someone who would rather go on fiancée Ruth's (Huberman) hen than anything remotely messy and, well, male.
As expected, (and, naturally, with the bare minimum of arm-twisting) Ruth convinces Fionnán of the merits of manning up for 48 hours as devoted-but-distant best friend and best man Davin (Scott) organises a thoroughly sensible itinerary involving more walking than just from table to porcelain in a bar.
Then Ruth's brother The Machine (McDonald) comes along.
The type of guy who probably slept out in the open at Féile in a bin liner, wedgied one of his teachers at the age of 14 and acted out the misheard Sawdoctors lyric "I have fallen for her mother, she can make her own way home" on one of many lost weekends, The Machine takes control of this band of (beta) brothers and decides he knows the best route to take. And he doesn't need a compass.
Co-written by director Butler and star McDonald, The Stag brings to mind Maeve Binchy's great riposte when someone would say that they could have written one of her books: "Yes, you could, but you didn't." Having the last laugh, Butler and McDonald's film has already been sold in Europe, the US and Australia, and there is enough here to say that this is a partnership worth developing. But if they are going to stay together, then they need to work harder on the gags.
While excellently cast and acted, The Stag does mild chuckles more than out-and-out hilarity. After an excellent start, the plot, like its characters, becomes a bit lost and lacks a big drama such as, say, someone falling down a well, an encounter with a doomsday cult or lost hen party or hydroponic hijinks with the owners of a grow house. Clichés? Sure, but no worse than the male nudity on offer here. With the exception of Borat, when was the last time that fellas in the nip were truly funny?
Ultimately, The Stag is far better at sentiment than slapstick, suggesting that Butler and McDonald should give something more serious a go in the future. From pressure cooker situations between friends to the corrosive worry and fear of the recession, the serious moments here are the most memorable, with all the characters highlighting the danger to Irish males of keeping it all in.
If someone in Row L realises the same, then that really is a good night out.