I take my hat off to Fiona Young.

It's her job to teach binmen and taxi drivers to be polite and friendly to tourists during the Commonwealth Games. I watch with trepidation as she explains to 10 of Glasgow Taxis' finest that they must not turn the radio up or the intercom off when they have a tricky passenger in the back. Instead they should chat with them, be helpful and above all - smile, smile, smile.

I glance around dubiously. It looks like an episode of Glaswegian Grange Hill - and this is detention. There's a fair bit of eye-rolling and lots of arms are folded. After all, this is common sense, isn't it? Be nice to people. But this is Glasgow. And Glasgow is a friendly city. So why are we teaching Glaswegians to be friendly?

For Back To Charm School, my documentary for the BBC's World Service, we discovered that 48,000 people in the city's service industry - binmen, waiters, shop assistants - are going through the Glasgow Welcomes course.

Young is evangelical about it. She tells me the training is essential because customer service needs to be improved; that some businesses didn't even think they were part of the service industry and were doing fine, thank you very much.

Enter the Glasgow Welcomes course, based around Disney principles. Every customer is given a standardised experience centred around courtesy, efficiency and performance. So does that leave any room for individualism or a bit of indecipherable Glaswegian? Yes, says Young. "We don't necessarily want people to say, 'Have a nice day' - we just want visitors to go home impressed."

Back in the training course, the taxi drivers and supervisors have been cooped up for far too long in front of a Powerpoint presentation and are going rogue. Their patter has us all in tears. I laugh so much I forget to take any notes or ask any questions. I salvage the situation by button-holing Jean Duffin, taxi driver of eight years. What does she think of the course? She says it's helpful to remind people about the basics, but worries about snuffing out the character of Glaswegians. "You've got to be yourself," she tells me. "We have more to offer as individuals."

Of course she's right. Glasgow is famous the world over. Most people have a pre-conceived idea of what it will be like. It will rain, everyone will talk about football, some people will talk too fast and you won't know what they said. Whether that's accurate or not doesn't matter. Tourists are coming here for a specific experience, with people at the heart of it. If they're greeted by Disney automatons, they'll be disappointed. But I get the feeling that won't happen. Because every service worker I meet tells me so.

On balance, I think this kind of training - seen in Beijing before the Olympics - suggests a degree of socio-cultural panic amid the meticulous preparation. But to what extent is the delivery of these courses down to a complex about not being good enough and how much of it is a desire to teach people to do their best? How much of the opposition is a chip on our shoulder and how much is confidence that we are already polished enough?

Binmen are going to be sent on the course too. Apart from loading lorries and sweeping the streets, they'll probably get asked for directions. The man in charge of keeping the east end's streets clean during the Games is John Quinn. He talks proudly about the Golden Mile around the venues and makes a face when I ask about the course. "It'll work to an extent," he says diplomatically, "but you want people to experience the real east end."

Out on a shift with Raymond and Gary, sweeping the streets, I ask if they got any Games tickets. No, because they'll be working. They say unlike the police they won't get fed while on shift and will have to buy their own food and drink. "We're the lowest of the low - we're the cleansing," they say bitterly. But they tell me they understand how important their job is - because after all "in Glasgow, you're never more than 10 feet away from a rat - and that's just the people!"

I laugh like a drain but later wonder if someone from Saudi Arabia or Gambia would understand that line. I conclude probably not. I also reckon that joke would have given Fiona Young palpitations.