Aidan O'Brien happy to prove Think critics correct

For all his highly respectable endeavours since arriving from Australia, it had become difficult to resist some kind of sardonic subtext in the naming of So You Think. Yes, the imported champion had won four Group Ones for Aidan O'Brien, but met an aggregate of just 17 rivals in the process – many strictly below the elite standard. And after not quite matching his billing, at short odds for several other top prizes, this big, dark, gleaming beast was in danger of becoming known as So You Thought.

Yesterday, however, he redressed last year's narrow, odds-on reverse in the Prince of Wales's Stakes with a decisive defeat of Carlton House. Quite how thorough a transformation this represented, it is hard to say. The horse who beat him that day, Rewilding, broke down in his next start, and they had finished miles clear of the rest – including a couple who got rather closer this time round. But his trainer sounds adamant that So You Think is only now piecing together the fragments of his southern hemisphere reputation. Never slow to reproach himself, O'Brien was at extravagant pains to abase himself before those Australian critics who had perceived some loss of zest in So You Think.

"We've had him a year and a half and that's how long it has taken me to learn how to train him," he declared. "I'd just like to say sorry to all the Australian people, that I made such a mess of it for so long. We were rightly getting a fair hammering from them but we needed to pull our socks up. I was probably working him too often, too long and too hard. I was killing him by making him grind, but even so he was very competitive."

Ryan Moore can only be vexed by any such transformation. Last year, he committed So You Think a long way out and was cut down late by Rewilding. This time, riding Carlton House, he burst through along the rail halfway up the straight, only for the favourite to find extra for Joseph O'Brien. With that raking stride and wild mane, So You Think presented a formidable picture as he surged just over two lengths clear.

John Magnier and his partners will soon repatriate So You Think to Coolmore Australia to begin his stud career, and quarantine restrictions will confine him to a swansong in the Coral Eclipse Stakes at Sandown a fortnight on Saturday. As things stand, he is unlikely to find Frankel lying in wait, with Sir Henry Cecil seemingly inclined towards the Qipco Sussex Stakes at Goodwood before finally stepping up in trip at York.

Though the monarch was disappointed in her hopes for a first Group One winner on home soil since 1977, the dash shown by Carlton House suggested that she need not wait much longer. The runner-up's trainer, Sir Michael Stoute, offered no excuses but it would be no surprise to see him suggest a further drop in trip. Conversely, Godolphin should consider supplementing Farhh to the King George VI and Queen Elizabeth Stakes, over another couple of furlongs back here next month. Even in meeting his first defeat, Farhh reached a new peak after missing the break and then meeting traffic in the straight, before powering home for third. Godolphin have finally found another legitimate horse for this level, and it must be hoped that Sheikh Mohammed enjoys better fortune with Farhh than he did with Rewilding.

His wife, Princess Haya, had earlier led in Joviality after her success in the Windsor Forest Stakes. John Gosden, in complimenting his patrons' mutual horsemanship, disclosed that the Sheikh had won a 160km endurance race over the Italian mountains the previous day.

The other races confined to fillies were won by Ceiling Kitty, trained by Tom Dascombe for Andrew Black, co-founder of Betfair; and Duntle, trained by David Wachman, for the Niarchos family. And, not content with giving his son a first Royal Ascot success on So You Think, O'Brien afforded the same breakthrough to that Ballydoyle stalwart, Seamus Heffernan. Riding in the colours of the trainer's wife, Annemarie, Heffernan won the Jersey Stakes on Ishvana.

Tom Tate meanwhile confirmed how a barren season belied his dexterity when adding the Royal Hunt Cup to Prince Of Johanne's success in an equally impossible stampede, the Cambridgeshire, last autumn. Tate hasn't suddenly forgotten how to train, any more than O'Brien.