You know the type - if it's menswear then they dismiss trends with a simple "it looks a bit gay" and if womenswear happens to be their target du jour then they hit you with the alternating "makes your legs look fat"/"it clings in the wrong places".

I hate to say it, but when it comes to current fashion, it looks like they might have got one right. Never mind just the doubters, women up and down the country have been more than a little discontented by the current trend for sack and tunic dresses.

The problem is that teamed with leggings as per the current vogue, you're left with a look that isn't actually all that flattering.

There is no doubt that tunic dresses make you look stocky and sack dresses make you look pregnant, but then to combine it with a garment such as leggings that frankly, only the sveltest of dance students can carry off, is just asking for trouble.

That said, it doesn't matter. Because once a look has caught on, then you have the fashion equivalent of a level playing field. If your leggings make your calf muscles look like Thierry Henry's then chances are they do the same to the woman next to you.

For that brief moment in time when an item (no matter how unflattering) is considered unquestionably "on-trend" then normal considerations are cast aside.

This level playing field theory is an example of what psychologists call groupthink. It's basically where we cast aside what we know to be good for us in order to conform to mass consensus.

I admit, the bulk of such research has tended to be focussed on considerations such as Hitlers rise to power or football hooliganism, rather than the fact that the empire line makes you look pregnant. But still the parallel is there.

Right now, it's a look literally everyone is sporting, and as such everyone looks like they are just entering their second trimester! Case in point, at a recent focus group for Queen of Suburbia, I overheard a collection of trendy young things comparing with ill-concealed pride, the number of people who had asked them the dreaded when's it due question that week.

The subtext is clear. If people aren't offering you their seat on the bus/tube/metro then you just aren't fashionable enough!