Indeed, it is fair to say that from the red rose perspective, Gregan is one of the least amusing of this Saturday's opponents. He made his pitch for Wallaby sainthood early - as a 21-year-old rookie, he produced the mother and father of all try-saving tackles on Jeff Wilson as the great All Black wing was about to win the 1994 Bledisloe Cup for New Zealand - and over the course of 40 subsequent performances he has earned himself a jealously guarded reputation as the engine of what is now a veritable Rolls-Royce of an Australian side.
And what an engine: small and compact but positively bursting with piston power. Enzo Ferrari would have loved the guy to bits, just as Bob Dwyer does. "Take a look at George," the 1991 World Cup-winning Australian coach once said. "You think he's a pushover? A little on the fragile side? Don't even dream about it. George is the ideal modern rugby player personified: powerful, dynamic, perfectly conditioned. He sets the standard in terms of physical fitness and resilience."
Increasingly, he is also setting the standard in contemporary scrum-half play; in the opening Test against Ireland in Brisbane 11 days ago, he produced a display that put the "zeit" in rugby's "geist". His passing was efficient rather than stunning; he is no Nigel Melville, let alone a Gareth Edwards or a Kenny Catchpole. There was nothing startling about his kicking, either: he was accurate enough when he put boot to ball, but his punting did not bring the Irish to their knees. What made the tourists long for home was his energy, his muscularity, his relish of confrontation. There is a touch of the nasty about Gregan and he does not mind who knows it.
"That's today's game, isn't it?" he acknowledged after a particularly fierce Wallaby training session at Sydney's Concord Oval this week. "The intensity of Test rugby - or non-Test rugby, come to that - is increasing all the time, almost match by match. The scrum-half's role has certainly changed since I made my debut against Italy back in '94. Defences are so flat now; the first-up tacklers are on you the split-second you get the ball. To survive, you constantly have to work out new ways of committing defenders, just to keep a move alive. And when you're committing a defender, you're asking to be tackled. That's the way it is."
Born in Zambia a little over 26 years ago - his parents decided to uproot and move to Canberra before their son's second birthday - George Musarurwa Gregan learned his rugby at St Edmund's College, one of the capital city's more renowned union-playing schools.
An exceptional practitioner of the short game, he made the national squad for the 1994 Hong Kong Sevens and captained them at the same event the following year. He was no great shakes during the last World Cup (neither was any other Wallaby, of course), yet the immediate advent of professionalism sent him spiralling onwards and upwards. A key influence behind the ACT Brumbies' rise to Super 12 prominence, he was named Player of the Tournament in 1997. Later that year, he won Australia's Players' Player accolade and served a stint as his country's vice-captain.
He vehemently denies that the Wallabies have 65 back-line moves in their repertoire; indeed, he finds the very suggestion offensive. "I know David Campese said that the other week, but it just goes to show how long Campo has been out of the Wallaby set-up," he said, only half-joking. "We've cut the planned moves right back over the last season or so and our current set of calls wouldn't be anywhere near 65. We're trying to get to different places now; it's all about reading each other and playing it off the cuff. You need to control the ball, of course; we didn't control the ball in the second Irish Test and ended up with a fight on our hands. But we don't stick rigidly to any plan or formula. Structured ad lib? Yes, that sounds about right."
Gregan spent the Irish series nursing a new outside-half, Nathan Spooner, through his Wallaby initiation, a task that suited his naturally authoritative manner. "It wasn't just me; the whole team took it on themselves to pull Nathan along," he pointed out. "But as his half-back partner, it was down to me to free up some time and space for him. Let's be honest here. A new cap has enough flying around in his head without his closest colleague selling him short and making life unnecessarily difficult for him."
This Saturday, though, he goes in alongside a player with far more of a past. Tim Horan, repositioned at stand-off in place of the concussed Spooner, has been playing for the Wallabies since 1989, when he made a Bledisloe Cup debut as a teenager, and has 69 caps in his kitbag. Not even Gregan, the very epitome of the chopsy scrum-half and an image of self-assurance, will be telling him how to play the game. "In so far as I have a mentor, Tim is it," he admitted.
"I spend time with people like him and Phil Kearns, guys who have won a World Cup and done pretty much everything in the game. They can put me right on things because it's hard to imagine having a problem that they haven't encountered and dealt with themselves.
"It's good to see people like Tim getting themselves up for Test rugby, even though they've been doing it for years. Mind you, this game against England is huge, just as the Tri-Nations with South Africa and New Zealand is going to be huge.
"People ask me if I'm looking forward to the World Cup in October and I say: `Hey, that's miles away. Look what we've got in front of us before then'." England are probably saying the same about George Gregan. He may not be the biggest rugby player around, but as Jeff Wilson will confirm, he takes an awful lot of avoiding.