I’m quite partial to a bit of magic. Quite a lot of the psychologists I know have a passing interest in the subject. I think it’s all part of a fascination with how the mind works: that balance between our willingness to believe the incredible, it only works if you suspend your disbelief, coupled with the side darker side of human nature – our enjoyment and skill at deceiving others.

Of course the fun with magic is wondering how it’s done. Even though we know it’s a trick, and even when you know how a trick is done, it’s still entertaining. If you do know what’s happened you get to swap sides as it were and enjoy the experience as the magician would – the pleasure comes from seeing the other people baffled and amazed.

I vividly recall watching a magician on a cross-channel ferry; the room shape wasn’t ideal and, by chance, I was watching from a point where I could see his assistant climb through the fake back of the box she was supposedly disappearing through (I hope I haven’t spoilt anything for anyone there). Much like watching a car crash – I couldn’t stop myself looking but it wasn’t pleasant.

All of which brings me to Nando’s (Cambridge).

I spent a number of years working for a “casual dining” restaurant – the industry’s term for those outlets that span the gap between fast food and proper dining (although as with most industry terms no one can quite agree on the definition or who it includes). So when I visit a restaurant I know how things are done – what matters is whether everyone can see them.

Despite their extensive chain (over 200 restaurants in the UK) I’d never been to one before. Why? Probably because of where I first encountered them. The old adage that “first impressions count” is psychologically verifiable. What we encounter first sets up our expectations of what we’ll find and we look for the evidence that supports our first view.

I first encountered Nando’s in Shepherds Bush, London: a dismal, grimy road littered with chicken restaurants named after random cities and states from the Deep South of the USA. I was happy to chuck Nando’s in with the company it kept – another psychological inevitability. When I heard, back in 2002, that someone had been shot there it didn’t exactly force me to reconsider my feeling about the place!

Why did I change my stance and go? Well I didn’t really.

I had decided to take my son to Frankie & Benny’s but they were “full”. I say “full” because the restaurant looked empty but we were told there would be a fifteen minute wait for a table. Whether this was because they were short-staffed, had a huge number of reservations all due in the next five minutes, or because they were simply trying to get extra revenue from people by stalling them so they would buy an extra drink I couldn’t say. I do know that restaurants like theirs make huge margins on drinks.

So, because it was next door, and because we weren’t in Shepherds Bush and Cambridge isn’t a gun crime hot spot, Nando’s it was.

The first impressions were mixed. The restaurant looked clean and well ordered, but the overall feel of the lighting and décor was gloomy; we were eating at 6.30 in the evening, but the environment felt more appropriate to later at night.

A waitress who was friendly explained how it worked and I got my first glimpse at the operating model – Nando’s is a cleverly engineered to keep costs down. You order your food and drinks at the counter and it is delivered to your table – this keeps contact time with customers to a minimum and cost of labour low.

Whilst the menu was physically large, the choice was very small. Variation came in the form of heat options; a chance for groups of guys to be competitive and go for extra hot PERi-PERi sauce if they’re feeling brave.

Also, many of the diverse ethnicities in the UK have a palette that prefers more piquant offerings than traditional British cuisine favours. For my money this is a smart thing for any restaurant to do; it keeps costs down and should mean that what they do offer is good.

We ordered and were greeted at the counter by a range of up-sells; the olives looked too good to resist and we shared a bowl. They were as good as the food that arrived a few minutes later at our table.

But here’s where things went wrong.

The children’s meal option that my son had selected included a choice of two desserts; they had neither. The person at the till tried to make it look as though they had just run out, but her language and body language betrayed the fact that this wasn’t new news.

Of course, sometimes things run out, but when the menu is so restricted they really shouldn’t and if they do an alternative should be offered. It took me saying “you need to replace that with something else” for us to get a juice drink substituted.

Now, just like on the boat when I saw the magician’s assistant climb out in the disappearing act, I got the distasteful sight of cost management in action.

What Nando’s was trying to make out of customers like me illicitly it should make by understanding consumer psychology and behaviour better. The clue to Nando’s increasing their profit was evident when we walked in. The mood was out of step with the time of our visit.

By using the right peripheral associations with lighting and music, Nando’s could make the ambience fit diners moods and get more people passing through more quickly when they’re busy and spending longer (and consuming more) when they’re not.

The link between visual and auditory cues and consumer pace are well established. By being slightly more sophisticated in its approach Nando’s could make an average experience better AND increase profits.

And, readers of Mindshop! aside, no one would see that particular rabbit being put in the hat before the show: instead customers would feel better about their experience and choose to come back more often.