The debate has started. Is Rory McIlroy making a mistake by joining the PGA Tour at this stage of his career?

Did he say: "In five years I'll be beating these guys"?The Guardian's Lawrence Donegan thinks the youngster may well have boobed by trying to play both the US and European tours.

There is no doubt, as Lawrence points out, that spending lengthy periods of time in the US means you simply don't get home to see your coach as often as you might like. Just look at Harrington's disastrous DIY swing tweak this year. Then there's the travel, as McIlroy's World Cup partner Graeme McDowell can attest after a nefarious PGA Tour foray cost him a Ryder Cup place at the K Club in 2006. McDowell's manager at the time was Chubby Chandler.

Maybe that's why Chandler was trying to persuade McIlroy to stay put in Europe and his Oct 21 email to the SportsBusiness Journal telling them that "Rory has decided not to join the PGA Tour in 2010" appears to have backfired on him spectacularly.

When I asked McIlroy about it before the Volvo World Match Play in Spain, he said: "I saw that. That's not accurate." And he said it in a hurt tone that hinted that he was not totally happy that a decision had been taken on his behalf or that he was being railroaded into doing something he was not quite sure he really wanted to do.

Given his inexperience, you could argue that he might be better off winning a few Italian or Portuguese Opens and improving his putting before committing to the PGA Tour. Then again, we are dealing with an extra special talent.

He has agonised over this move and being 20 and ambitious and wonderfully talented, he's decided he's going for it. 

It was a decision made easier, no doubt, by his closing 63 in the HSBC Champions on Sunday. Knowing McIlroy, he truly believes he is right. 

It's not a prerequisite for good golf, but McIlroy is highly intelligent - a gifted student who didn't much care for school but still achieved outstanding SAT results when he was toying with the idea of going to East Tennessee State University.

He decided not to take that route, left school around his 16th birthday and was a full time golfer in 2005. It was a decision that backfired in the short term because he irked the Walker Cup blazers by skipping a series of big championships to play in a few European Tour events on invitations.

England's Oliver Fisher, not McIlroy, became the youngest Walker Cup player in history.

McIlroy shot 61 around Royal Portrush soon afterwards, left Peter McEvoy and Garth McGimpsey to rue their decision and waited another two years to turn pro.

McIlroy's father Gerry believes Rory's non-Walker Cup selection in 2005 was the best thing that ever happened to a kid who listens, weighs up his options and makes fearless decisions.

Over the years, some of those decisions have been questionable but McIlroy has never doubted his own ability.

Can he putt better? He must. Will America help? He has to go there to find out.

He could have been forgiven for going backwards last year but fought his way out of a slump instead. In fact, he emerged from that slump on his own initiative by seeking out Paul Hurrion for help with his putting. No agent interference there.

That gesture made a deep impression on Padraig Harrington.

The new McIlroy reappeared in the 2008 European Masters at Crans, blew the tournament but walked down the mountain a man of 19.

His critics will say that he let three of the biggest events in Europe get away this year - the European Open, the BMW PGA and the Dunhill Links. But he has played unbelievably well without ever appearing to hit top gear for all four rounds and can become European No 1 next week.

He has played 34 events since he handed Jean Francois Lucquin the title in Switzerland 13 months ago and achieved  the following results:

Wins 1 (Dubai)

Runner ups 2

Top 5s 10 (13 total)

Top 10s 5 (18 total)

Top 20s 6 (24 total)

Missed cut 2.

No doubt the US media will start asking questions, if he fails to win on the PGA Tour before the Masters.

I once asked him if he felt he was as good as Ollie Fisher and he looked at me sideways and said they were pretty well matched. As Fisher travails in Hong Kong this week to try and salvage his tour card, McIlroy is on the cusp of becoming the youngest European No 1 since Seve. 

You fear for him should things go pear-shaped in America but he's been on an upward curve his entire career and the sky's the limit. 

America can wait but when you have a talent that big, why hide it?