What do you need a degree in to be an Irish brain surgeon?
Woodworking.
How do you sink an Irish submarine?
Knock on the hatch.
Did you hear about the new innovation on Irish submarines?
Screen doors.
How do you burn an Irishman’s ear?
Ring him while he’s doing the ironing.
How do you drive a Scotsman crazy?
Put him in a round room and tell him to find the penny in the corner.
How do you drive a Welshman crazy?
Put him in a room with two shovels and tell him to take his pick.
This. A thousand times this.
An Englishman, Irishman, Scot, and Welshman all walk into a pub. They each order a pint and drink without incident, proving that people are pretty much the same everywhere.
Lenny Bruce on how to work in the UK.
I’m going to go against what the majority are saying here.
As a lifelong UK citizen and enthusiastic comedy fan can I say that there are few things funnier to a UK audience than having the piss ripped out of them mercilessly. It has to be done with affection and a “knowing” tone but you can definitely be brutal and offensive and we will love you for it.
Mean jokes in Scotland? yep.
Drunk jokes in Ireland? yep.
Sheep-shagging jokes in wales? yep.
It is all in the delivery. It has to be done in absolute earnestness but whilst also getting across that you don’t mean a word of it. You are playing a caricature of the idiot foreigner, taken in by the stereotypes fed to you.
Of course if they are ham-fisted comedians then anything they say may fall flat.
That’s a joke. 
Speaking of sheep-shagging jokes, a UK audience might enjoy this:
An Australian on holiday in New Zealand is walking though the countryside when he spies a local farmer banging away on a ewe.
Outraged, the Aussie approaches the farmer and says “Y’know, mate, where *I *come from, we *shear *those!”
“Bloody hell!” says the Kiwi, panting. “I’m not shearin’ this with anybody!”
Aye, bonnie Scotland—where men are men, and sheep are nervous!
Odds are they’d hit the nail on the head in each case. 
Was it George Carlin who said the word “dude” has at least fifty different meanings in California, depending on how you say it? F’rinstance:
“Hey, it’s great to see you again after twenty years!” = DUDE! 
“Hey, that’s a really great suit you have on!” = Duuuuuuuude! 
“Hey, is that you hiding in the closet with a butcher’s knife?” = … Dude? :dubious:
An Irishman and a Scotsman walk into a bar. The Scotsman yells out, “Drinks for the house, on me.” The newspaper headline the next day said, “Irish ventriloquist found beaten to death behind pub.”
“Hey, MacLeod, Get offa my ewe!”
An Englishman, an Irishman, a Scotsman, and a Welshman are sitting in a waiting room when a fly buzzes in.
It circles the Englishman, and he brushes it away.
It circles the Irishman, and he brushes it away.
It circles the Scotsman, and he brushes it away.
Finally, it circles the Welshman. He grabs it, looks at it for a second, and pops it into his mouth.
A minute goes by, and another fly buzzes into the room.
It circles the Englishman, and he brushes it away.
It circles the Irishman, and he brushes it away.
It circles the Scotsman. He reaches out and grabs it and says “Anybody want to buy a fly?”
Have you heard about the new Scottish automobile?
It doesn’t just stop on a dime, it picks it up!
Really NSFW:
[spoiler] After serving gallantly in the Falklands War, a Scottish Sergeant Major is called into his superior’s office and told he’s been granted a bonus, and can have it paid out any way he wishes.
“SIR!” says the Scotsman. “I’d like £100 paid out fer every inch between me balls and the tip of me dong, SIR!”
The officer agrees, and lifts up the Sergeant Major’s kilt to measure him.
“Egad, man!” says the officer. “Where are your balls?”
The Sergeant Major snaps to attention and says “Goose Green, Falkland Islands, SIR!”[/spoiler]
Three old farts are sitting in an Officers’ Club in London, smoking and drinking and talking about their past exploits.
“Y’know,” says the first gent, “I’ve been in the army thirty years, soldiered all over the world, and for my money, the best damned soldiers in the world are the Ghurkas. You know, those little brown chaps. They’ll trot all night through the jungle, never tire, go on to attack a machine gun with a machete… Magnificent!”
“No,” says the second, “For my money, the best damned soldiers in the world were the Waffen SS. Absolutely fearless, fought to the last man, never disobeyed an order… Superb!”
“No,” says the third, “afraid I must disagree with both of you. As far as I’m concerned, the best damned soldiers in the world are the Irish. Simply without parallel… Provided, of course, they’re commanded by White officers!”
Seriously? Just look at the common denominator of all those tired old “paddy irishman” jokes, then consider that some blow ins who got their mate to google some jokes are going to force them into their act. It would go down like a lead fucking balloon.
Remember, just because we can laugh at ourselves doesn’t mean you can laugh at us.
Oh we love having the piss ripped out of us. But I would wager that the scenario noted in the OP will be neither knowing, earnest nor funny. Got their mate to google a few paddy Irishman joke to oh so naturally insert into an act? Good luck with that.
Its a real shame I wont be able to get a ticket for this tour, which promises to be really unforgettable. The band members in particular will cherish memories of it for the remaining seconds of their lives.
If you’re a friend of the band, be a real friend and make them not do it. There’s a big difference between relating to people with affection and humour and delivering rehearsed crowd-sourced jokes between songs.
I have experience in this field.
Making ill-advised jokes, I mean.
Just don’t. It never turns out to be worth it.
What am I missing here? I don’t get it.
WELSHMAN: I’ve got Tom Jones disease.
IRISHMAN: Is it rare?
WELSHMAN: It’s not unusual…