Who's the musical genius: Bob Dylan or Bob The Builder? And what about Mr Blobby? Does he ever have a few drinks and start boasting he's better than The Who?

Well, who knows? Certainly not us. We, the general public, are in no position to pronounce on musical talent because we're the dafties who've pushed those joke figures into the coveted No 1 spot whilst denying the same to giants like Dylan and The Who.

So what are the rules for getting a hit song? If it's not 'Be A Novelty TV Character' then what is it? How To Make A Number One Record (BBC4) tried to work out the mixture of luck, talent and clever PR tricks which push records to the top spot.

Britain has had 1,300 No 1s since the charts began. 'There is a science to it', insists an academic who studies the patterns in popular music, but do we want to accept that? Wouldn't we rather think songs charge to the top based on ingenuity, melody and wonder? Maybe, but Mr Blobby made it, so there must be a bag of tricks here.

One of the quickest ways to get to No 1 is to appear on Eurovision. At least, this used to be a route to success until Eurovision became laughable. In the old days it produced hit records like Waterloo and Puppet On A String whereas now it'd be hard to imagine a respectable artist volunteering for that contest.

Why would they, when there's a far more ridiculous, and lucrative, contest in town, The X Factor. TV talent shows are another path to No 1, though this is hardly a recent development, with Opportunity Knocks giving us a No 1 record in the 50s with singer David Whitfield. Mercifully, though, their grip seems to be loosening, with the public rebelling against X Factor's sense of entitlement which means they routinely hog the Christmas No I spot. The show devoted a nice segment to the social media campaign to prevent the X Factor Geordie poppet, Joe McElderry, from festive chart success.

You could also bulldoze your way to No 1 by linking your record to a film (Love Is All Around), an event (World In Motion), a crisis (Do They Know It's Christmas?) or the sudden death of a redundant aristocrat (Candle In The Wind). There is nothing to which you may not hitch your wagon in the pursuit of stardom.

Of course, these days there are no 'records', just invisible files to download, and one of the experts on the show made a very revealing comment on that subject. He marvelled that, upon hearing a song you like, you simply pull out your phone and 'get it instantaneously without any thought.' How telling: 'without any thought'. There is no more waiting for Saturday to head into the record shop to queue up to buy the song. In short, there's no sacrifice or effort. You don't even need to like the damn thing. Your fingertip hovers over the screen….it's only 99p….I may as well get it. Tap! The song is yours. Did it really merit a purchase? Does it truly deserve your little shove along the road to No 1? Well, who cares? It's only a few pence. It's only a tap on the screen.

Yes, we don't buy 'records' now, so the show's plentiful footage of us all scrambling, browsing and queuing in record shops was nostalgic but no longer relevant, as was the furious importance of getting a spot on Top of the Pops. Being on display in the shop, or on the BBC stage, were invaluable to an artist, but now are largely meaningless.

This was all rather sad. The classic routes to success are mainly redundant and it's all about what Simon Cowell decrees we should listen to. If this dented the romance of music somewhat, nothing was more guaranteed to strip the remaining magic than a beaming Noddy Holder saying of his Christmas hit, 'It's ma pension plan!'