Katy Guest: Don't mess with my happy ending, doctor

So romcoms are not true to life. That's the point

Thanks a bunch and bah humbug to the scientists at Heriot-Watt University in Edinburgh, who have unveiled their latest research into spoiling Christmas. Dr Bjarne Holmes and his team have studied 200 volunteers so that they can debunk a sentimental and long-cherished festive myth. They say that romantic comedies are rubbish, romance is dead and there are no such things as happy endings in the snow. Next from the Grinches who stole Christmas: there is no Santa Claus and goose fat causes obesity.

Dr Holmes – a sort of Richard Dawkins to Richard Curtis's God – seated 100 students in front of a marathon parade of romantic films (presumably he was sponsored by Häagen-Dazs and Kleenex) and concluded that movies such as You've Got Mail and Runaway Bride promote "unrealistic expectations" about relationships. Well, I'll go to the foot of our stairs.

"Marriage counsellors often see couples who believe that sex should always be perfect, and if someone is meant to be with you then they will know what you want without you needing to communicate it," he explained. Yes, and shops often see people who believe that it should always snow at Christmas and that little elves will sober you up in time to get the last train home. It's OK: they stop believing it on New Year's Day and go back to being grown-ups again.

Romantic movies like the ones described by Dr Holmes succeed precisely because people are all too well aware of the real-life alternative. We get the picture: life is not an Andrew Davies adaptation. It doesn't all end with the wedding. "We need to talk" in the run-up to Christmas, is not going to lead to a public declaration of undying love in the snow. We are not turning to Bridget Jones as a gritty, fly-on-the-wall docusoap.

The formula for the perfect romcom takes all of this into account. Just as in real life, boy meets girl; boy engages in months of verbal fencing with girl; boy and girl drink eight pints of Stella and have weirdly accomplished movie sex; boy loses girl because boy doesn't know what is good for him. Unlike in real life, boy realises his mistake and passionately reclaims girl, preferably during heavy precipitation and in a Santa hat. Unlike in real life, he does this before he accidentally marries the wrong woman.

The last minute dash to the airport/ railway station/school Christmas play to scoop up the dejected beloved before it is All Too Late is a critical plot-shift device in the classic romcom; like in a boyband song when the key changes and they all get up off their chairs. It is the Richard Curtis ending that in real life we all so richly deserve but seldom receive. And, in a credit crunch year, it is at least free – barring the cost of the Santa hat.

The Christmas romcom is the grown-up equivalent of leaving out a mince pie and a sherry for Santa because, once a year, it is really nice to sod reality and believe in happy endings. Dr Holmes and his accomplices should let it be. Still, at least they haven't been persuading volunteers repeatedly to "electrocute" each other, as scientists at Santa Clara University have been doing this year. Now, there is a definition of the way relationships work in real life.