"They seem to think I'm somebody important. I'm going to play along with it." Gary Barlow's words as he arrived for a visit with a Solomon Islands tribe seemed particularly apt. Not only did they sum up his experience of filming this Jubilee-themed documentary, or indeed Barlow's career to date, but also the entire basis of the British monarchy.

In a day full of Jubilee TV, Gary Barlow: On Her Majesty's Service achieved the honour of being the most nauseating show of all yesterday. It was the story of Barlow's efforts in recording Sing, the smash-hit number 11 single he co-wrote with Andrew Lloyd Webber to mark Queen Elizabeth II's 60 years on the throne.

The documentary involved Barlow visiting various Commonwealth nations - Jamaica, Kenya, Australia and the Solomons - to record music to be featured on the song. It wasn't exactly in keeping with the Queen's renowned love for the Commonwealth - and was a bit rich for someone from Frodsham - for Barlow to describe his settings as "the middle of nowhere" on more than one occasion, but he at least brought an admirable level of enthusiasm to the task.

The whole affair was stage-managed, of course. Barlow didn't just happen to come across a fully-formed choir in a Kenyan village with an eerily encyclopaedic knowledge of the Queen, I assume, or a blind Aborigine halfway up a mountain in the Australian outback with an acoustic guitar and interpreter handy. Nor, presumably, were the percussion band living in the slums outside Nairobi - among the poorest places on the planet - so deliriously happy to be sampled on a track written by two millionaires to celebrate the continuing reign of a billionaire.

There were plenty of other cringeworthy moments. Barlow laughed at the idea of a Masai warrior having more than one wife, as if it were the most absurd cultural practice - bearing in mind Barlow is a judge on the X Factor - he'd ever encountered. In Jamaica, Barlow ran into Prince Harry and badgered him into revealing the musical tastes of his grandmother - shockingly, for those of us who like to imagine the 86-year-old Queen streaming The xx on Spotify, we learned that she didn't care much for modern music. Barlow even managed to get in a dig at the French along the way, for their outrageous habit of being able to speak English.

The emphasis on the 'native' elements of the Queen's realm belied the deception at the heart of the entire project, which is ultimately a throwback to an era when the white ruling class dominated these nations. Barlow and Lloyd Webber wrote the song, which is performed primarily by the British Military Wives Choir and the Sydney Symphony Orchestra. A few native musicians feature quietly in the background, without any discernible impact on the style or sound of the song. Only the Kenyan choir girl Lydia is given any prominence, in the introduction: Barlow felt it was important in giving the song that Commonwealth feel, and her pronunciation of the lyrics told the listener she was "from somewhere else."

Barlow acquired enough self-awareness to reflect at one point that, "I live most of my life not in the real world." But not quite enough to realise that this journey hadn't brought him any closer to reality.