Avoiding the wrong side of Johnno
It doesn't do to get on the wrong side of Martin Johnson.
During his years as one of the most respected players in world rugby union, his towering frame and ferocious frown were enough to strike fear into opponents, team-mates who stepped out of line, and hapless journalists.
The full force of the famous eyebrows can wither at 20 paces.
The man who won a stack of silverware for Leicester Tigers and the beautiful golden William Webb Ellis trophy for England was a formidable captain and, after two and a half years in the job, is establishing himself as a successful national manager.
But I have to confess I was feeling a little nervous as I sat down with him to reflect on his coaching career so far, at the start of a momentous year.
Martin Johnson leads England to World Cup victory in 2003. Photo: AP
The good news was that he'd given us an hour of his undivided attention. No coach or captain is ever at his most chirpy when he's having to work his way through a string of TV crews, radio interviewers and newspaper journalists, all asking variations on the same unoriginal questions.
I'd taken even more care than usual to come up with subjects that might engage his interest.
But within minutes of sitting down in a studio on the top floor of Broadcasting House, I realised I needn't have worried.
As the studio manager checked the recording levels, he chatted away about how almost no-one he knows calls him Martin. It's Johnno to everyone, apparently, even his wife, Kay.
And after we'd talked for a while about his approach to bringing on young Test players (he's more tolerant of those who wear white boots and spike their hair than you might expect), and whether they'd feel able to confide in him if they had a problem ("I do sometimes feel like a headmaster", he told me), I felt brave enough to ask him the burning question.
Do you think some people, er, might perhaps, maybe, find you just a little bit, y'know...intimidating?
"Yes, of course - I'm 6 foot 7 and I look how I look," he smiled. "People see you on the field and they think you're like that all the time, which of course you're not. But when you've got your game face on, you've got to be ready to play.
"When you're playing against similar sorts of animals, you've got to physically dominate the opposition. You can talk about rugby skills, but a lot of that is physicality. You need all sorts in the game."
It's perhaps an indication of Johnson's strength of character that he was prepared to take on the England manager's job, with no previous coaching experience, and at a time when the team was in the throes of an extended post-World Cup rebuilding period. It's been a learning process, and he's keen to take on board examples of great leadership from inside and outside rugby union.
"I love the Liverpool boot-room thing. You hear stories about Bob Paisley walking around in slippers and a cardigan - but he was the great tactician. And Bill Shankly was the great motivator. Mind you, it worked then - but would it work now?"
Times have changed in the world of rugby union, too. When Johnson started playing for Leicester, he was a bank clerk in Market Harborough, and relied on his manager to allow him time off to travel to games - even, eventually, to tour with the British and Irish Lions.
He still banks at the same branch, by the way - a loyalty which seems completely typical of the man.
And after Tigers home games, the players would take turns serving behind the bar at Welford Road.
Johnson wants to make sure his current crop of stars appreciate what professional rugby union has done for them.
"We were in camp in August, and I said to the players - don't talk to me about sacrifice, you get well paid to do this. You might be away from your loved ones when you're on tour, and that can be difficult. But the England women's rugby team gave up their jobs to play in the World Cup - that's a sacrifice. You're professional sportsmen, and privileged to do it."
There've been some remarkable highs and some distinct lows in the Johnson era so far. He relishes the victories over Australia, in Sydney in June and at Twickenham in November - although he confessed that, as Chris Ashton began celebrating his epic try with 22m still to run, he was internally shouting, "get it down!"
"I'm always saying, get it down - because it's not a try till you do!"
In contrast, there was the frustration of defeat in Dublin in the Six Nations two years ago, when his fury at Danny Care's sin-binning was captured by the TV cameras.
But Johnson is a devoted father, and should the strains of preparing England for the World Cup in New Zealand become excessive, he'll take consolation in his kids.
"My daughter is seven, and she understands winning and losing, but she moves on very quickly and that helps to take your mind off it. My little boy just wants to play with a ball - doesn't matter whether it's a rugby ball or a football."
So does he play with them in the back garden?
"Of course, yes."
And does he always let them win?
That famous face cracks into a huge grin.
"Not always, no! Because you've got to learn to lose as well. My little girl is competitive in everything. She doesn't like to lose."
I wonder where she can possibly get that from.
You can hear the full interview with Martin Johnson in Thursday's 5 Live Sport at 2200 GMT.