Thomas, just turned 22 but far older than he looks, has split Red Dragon rugby down the middle. For every believer who considers him to be a glorious throwback to the grand Welsh tradition of Carwyn, Dai, Barry, Phil and Jonathan - legendary Welsh stand-offs are only ever referred to by their first names - there is an agnostic who remains resolutely unconvinced.
His burden is made all the heavier by the fact that the sorcerer himself, Jonathan Davies, is back in the national squad and itching to play. Indeed, the 34-year-old maestro will be watching his young rival from the bench today, a startling role reversal that has led the more pragmatic Welsh followers to question the sanity of their national selectors.
But the Welsh coach, Kevin Bowring, is Thomas's staunchest ally. The engagingly polite and scholarly tactician introduced the vulnerable little rookie from Trebanos - 5ft 8in, 101/2st dripping wet - to Test rugby last season, watching him illuminate Twickenham with deeds of rare audacity in the tight struggle with England before disappearing into a pit of angst- ridden indecision in Dublin. Now, 10 months on, Bowring is gambling his reputation on a hunch that his protege's rehabilitation is complete.
He just may have backed a winner. Seven caps into his international career, Thomas is so self-assured, so completely at ease with the unique demands of his uniquely pressurised position, that it is hard to believe any of his illustrious predecessors were better equipped in the attitude department.
"The way I see it, I'm in the side to play my natural game," he says, acutely aware that there are legions of Welsh supporters who would prefer less imagination and more perspiration from their playmaker-in-chief.
"Obviously, any stand-off at this level has to be aware of the general game-plan and the various set moves incorporated within it, but Kevin has made it clear to me and everyone else why he wants me involved; he sees my unpredictability as my strength and he wants me to make things happen, play it off the cuff.
"To be honest, no one has ever tried to inhibit me or put the block on the way I play and if they did, I probably wouldn't take a blind bit of notice. That is not me being arrogant or big-headed - no one knows it all and I value advice - but I have never seen rugby as a treadmill. I do it for the enjoyment, the thrill of it. Besides, you have to create something with the ball in today's rugby because defences are so well organised.
"You can't work out everything on a blackboard. Scott Gibbs scored a cracking try against the United States last weekend from a pass of mine which, if truth be told, was pretty awful. It was down around his knees somewhere, but he had the hands to take it and the whole chain of events caught the Americans on the wrong foot."
To be sure, Thomas personifies the art of rugby far more than the science of it and that purist approach will almost certainly give the travelling legions of Welshmen a severe dose of the jitters today. He knows from bitter experience that in the eyes of the public, risks are worth taking only when they work; but then, he realised early that the stress of the win-or-bust approach went with the territory.
"I always wanted to play outside-half for Wales, right from a little boy, and I knew from the start that the shirt carried a great tradition with pressures and expectations to match. I thought I knew what being No 10 entailed, but looking back on last season's Five Nations now, I realise I wasn't as prepared as I'd thought I was, either on or off the pitch.
"Suddenly, there were a million interviews to do. Suddenly, I had television cameras following me to college. When you're not used to that level of exposure, it hits you hard. You end up not knowing which way to turn."
At that point, Thomas was playing for Bristol in the English First Division and living away from home for the first time. Now, he is back in west Wales with his parents - "great cooking," he smiles - and enjoying a purple patch with his new club, Swansea. "I'm more settled now, more prepared for whatever the next few months throw at me.
"I don't regret my time at Bristol for a moment, though. I owe them for the fact that I won my first caps from the Memorial Ground and a season in the Courage League was important experience. It was instructive to face the Guscotts and Carlings of this world, get up close to them and discover that, yes, I could catch even players of their quality on the hop if I got it right."
If he gets it right against Scotland, the long-promised Welsh renaissance will have a more realistic feel to it than at any point since the immediate aftermath of the 1987 World Cup.
"An away win in our first match would set everything up very nicely," he said this week. "A defeat would mean another wave of negative pressure, with the selectors being pressed to chop and change the team."
High stakes indeed. Given the fragile nervous disposition of a passionate rugby nation, it is just as well that Arwel Thomas feels more comfortable with those stakes than any of the thousands of red-scarved neurotics staring down from the stands.Reuse content