When you've been shopping non-stop for eight hours or you've splurged on a grande latte, eventually the inevitable happens. And when it happens, you'd better hope that you were born a male rather than a female.
Because in this city, men have - to put such matters as delicately as they should be put - lavatory licence. That means we usually come and go as we please with seldom a thought for possible impediments. Sure, every once in a while all the urinals and stalls are occupied, but a bloke only has to line up behind one individual - and never more than one - and the porcelain portal opens soon enough.
This is really good news for men because, as we've been whizzing indiscriminately for millennia, we wouldn't know what to do if faced with the kind of lineup I saw last Saturday outside the women's toilets in Sha Tin's New Town Plaza. It was so long that some of the women at the back were calling out their orders across to the nearby Pizza Hut. And their food probably would have been ready for them by the time they finally got out.
How can women hold on that long? I know men wouldn't be able to do it - everything starts looking like a bush when we have to go that badly.
The other thing I've noticed is that there are never children of either sex younger than five in the lineup. Why? My wife says she has never once seen a woman ahead in a queue give up her place to a woman behind, no matter how much the children of the woman behind are prancing, tippy-toeing, or scrunching at her feet.
With this type of scrupulous queue self-regulation it's no wonder that fathers are so often pressed into going shopping. And we thought that maybe we were there to simply give the thumbs up on every shoe that gets tried on. In fact, we're there to be pressed into action at the first sign of a child dancing to an emergency tune. And we should always leap into action with a smile. It's the least we can do.