The reputation still follows Donncha O'Callaghan as loyally as the paddling of ducks which he once inveigled into a Munster team room. Whereupon they promptly delivered their post-prandial offerings upon the floor.
His autobiography may be called 'Joking Apart'. He may stare from the jacket with those steely blue eyes. But he knows he has cried wolf once too often. Privately, he is a doting dad and a loyal husband. Publicly, he retains the image of a sporting Tommy Cooper.
Hell, everyone still thinks it was he, and not Paul O'Connell, the supposed epitome of intensity, who whipped down former Labour spin doctor Alastair Campbell's jogging pants in front of the world's press on the 2005 Lions tour.
He throws his eyes to heaven. "I still struggle to separate myself from that," he sighs. "It was probably always in me to be fair. I always liked having a laugh. But when I'm on, I take things really seriously. Like, when I'm playing ball, there's nothing in the world that matters more to me at that moment.
"You'd see it in the squad. Everyone gets put into certain brackets. Paulie's so straight-laced and they look at me and think he's the joker. But hang around with Paulie, he's an unbelievable messer, the worst. But I'm the one always asked about mad stuff and I'm thinking 'How well do these people f**king know me?'
"It doesn't really bother me now because I kind of just play up to it. It's easier to crack a joke, isn't it? Just give them the answer and everyone goes away happy. There's no real harm. I'll never fault it. I'm fulfilled in my career. Once people know there's the jokey fellah, but someone else who gives a s**t."
Maybe life taught him how to embrace fear with a laugh. Or, at the very least, cope with a smile. How else to confront tragedy as a five-year-old?
Hughie O'Callaghan was a hard-working husband to Marie, father of five kids -- four boys and a girl. A job with the Corporation appeared to provide some semblance of stability for the burgeoning family.
However, Hughie died well before his time. He was 40. Donncha was just five. Marie, Hughie's wife, wasn't even able to enjoy a pension. Donncha's eldest brother, 16-year-old Eddie, immediately quit school to assume the nominal status as the male head.
O'Callaghan's childhood -- and beyond -- would be framed by his father's absence. His wonderfully stoic mother would provide an omniscient grounding presence instead.
Despite his age, Marie told him straight out what happened. His father was gone. "Holy God needs him now," she said. The five-year-old wondered who was doing who a favour.
"She wouldn't sugar-coat it," he recalls. "I remember the morning so well. The aunts are in the front room and you just know that something bad is after happening. I went into the parents' bed and I could feel the cold of it. You pick up on a feeling.
"I remember after she spoke, though, I remember thinking we're going to be alright here. Mum's got me, you know. Looking back now, and when you've kids yourself, even just one, you wouldn't know how people function."
He remembers being in the church at the funeral. Everyone was crying. So he joined in. Still unsure as to what was really going on. The absence would fester as he grew older.
"You were always envious of the lads later on when their dads were coaching and all that. Just seeing the role that a father always played and you never had that.
"It's easy to say you can't miss what you didn't have. But when you're seeing your mates' dads every day ... I'll never forget Drico's oul' fellah hugging him when we won the U-19 World Cup. I remember thinking, I'll never have that.
"But it's the normality of it you miss too, telling people that your oul' fellah is giving you grief. I was fortunate to have brothers really, especially Eddie, a bit like a father figure I suppose.
"Everyone talks about Ultan from the rugby connection and I have followed his path in many ways. But if there was anyone I wanted to be like, it was Eddie. He's as a straight as a die, you know.
"It must have been awful for him, 16 years of age and he had to throw himself into it. He finished school straight away, he knew exactly what this meant. I didn't even know what was going on really."
Marie, like a more benevolent version of JB Keane's Big Maggie, assumed the role of matriarchal moralist. She defended her family to the ultimate, but not at the expense of decency and honour.
"If you got into a fight, the mom would go out and take on any of the neighbours and you'd be beside her, grinning, thinking I'm in the clear here," he says smiling at the recollection. "She's got my back here! But then you'd come up to the house and get worse punishment, you'd be nearly ashamed. She'd never let you away with anything."
The book details an idyllic upbringing, despite the obvious financial strains. It is not overtly confessional, nor scandalous.
In parts, it is quite evocative -- as when he tells of how he skipped one of his two school buses to hoard the extra fare. The driver of the No 5 still sees him around town and pokes his head out of the window to slag him that he should have charged the "small big lad" as an adult.
A normal life, but in many ways anathema to the prejudiced view Ireland has of its rugby heroes. "I was saying to Denis (Walsh, the book's co-author) that this was normal stuff and he was, like, I don't think so, kid! It was normal for me, though."
Normality, such as it was, ended when the fledgling Highfield talent won a scholarship to CBC as a 16-year-old. Now the very kid who slagged off the poshies would become one of them.
He dreaded his first morning, especially when he went sans blazer. He needn't have worried. Rugby was a common language. Science teacher Bill Guiney used to end his double class with a Super 10 video show, often scribbling plays on the blackboard to complement complicated algorithms.
At Bishopstown, he'd always be late for school, even though it was around the corner. It took two buses to get to CBC, but O'Callaghan would rock up half an hour early every day.
His rugby story is well-versed by now -- Munster, Ireland, Lions. His struggles have been less public. O'Connell and O'Callaghan are an established double act, but it is easy to forget how long it took the latter to become a fixture in Munster red and Ireland green. A startling lack of confidence in his own ability hamstrung him.
So, he worked harder than anyone else to compensate. And instead of carrying the ball, he spent his time mining the darkest rucks imaginable to secure it for others, an aptitude that matches his selflessness off the field.
"It happens in lots of people," he explains of his stilted confidence, perhaps stemming from his first, giant leap into the unknown at CBC. And his predilection for replacing nerves with a joke.
"There are times you're thinking are you really cut out for this level. I suppose I was lucky in that I always felt I was less talented than a lot of people I used to share the room with.
"So, I'd to make up for it with hard work. I always thought if I was fitter and stronger than most of them, I could stick with them. I knew I could make up for it somehow. That's probably the story of my career really. Not having supreme confidence in my ability was probably a good thing."
It's no big deal -- but wrestling the jersey from Mick Galwey was. Galwey, a garrulous, old-school type, naturally wanted to hold on to it and didn't necessarily feel obliged to offer a leg up.
O'Callaghan, teetotal and from a different generation, honestly details his frustration at waiting in the wings. Spurning the clichéd team spirit nonsense, O'Callaghan speaks of how he wanted to "put Gaillimh through a wall."
Now the boot is on the other foot. His place is no longer automatic. And he has no interest in patting his usurpers on the back. It's all about the jersey.
"It was so frustrating," he says. "I just wanted a break and didn't know how to do it. But it stood to me as a lesson. What I did learn from Gaillimh was how you respect the jersey, if not rugby learning. How you're supposed to conduct yourself.
"I'm unbelievably grateful for that. The suffering you go through beforehand makes it so special, If it's just handed to you, I don't know. Everyone's saying now the young guys should be given a go, but they have to earn it. Grab it instead of waiting for someone to go."
He's learned to maximise those talents. He spurned sports psychology and team-building in his early days, but has since seen its merits.
"I've gone full circle on sports psychology and team-building. I just saw the value in it and used better people, like Gerry Hussey and Enda McNulty. It's about my own internal self-image, concentrating on the things I do well.
"Everyone harbours doubts. So, it's just concentrating on the things I do well. I started to argue the point more instead of just saying it's a load of b*****ks. I suppose I adapted to it."
He takes out a video on his phone, Elbow's 'One day like this' accompanying a slideshow of all his best moments. And he's had them all. Heineken Cups. Grand Slam. Lions captaincy.
He's closer to the end of his story than his beginning. He knows that. His values, particularly those bequeathed by Marie, will trace his path back into the normal world where not all the rules of the dressing-room necessarily apply.
"I mean even if I was one for whipping down fellahs' pants, you'd get fired for that sort of stuff in the real world," he insists. "Probably arrested as well."
He won't play the Harvey Norman -- one year, no interest. That would "kill him." The addiction to winning still bites. Even if it necessarily means flirting with the agony of losing, as so graphically detailed after losing to Wales in the World Cup.
"Winning is great and there's a glow for a while," he says quietly. "But losing is f***ing hell. And it's a burden that sits with you for some time. What's that Lombardi quote? 'If you can accept losing, you can't win.'
"I'd do anything to avoid that feeling. There's nothing like it. People close to you don't know it. They don't know how much you suffer after a loss. And they never will. People tell you there's another match next week and you play along with that. But we know."
It still drives him. A serious man? You better believe it.
'Joking Apart -- My Autobiography' by Donncha O'Callaghan. Published by Transworld Ireland.