It was when the elderly Scotsman began a lurid description of having his ear syringing operation called to a halt by hair growth inside his ancient lobes that I choked on my spaghetti. I am not particularly squeamish but it was a detail too far at dinner.
Take a dozen individuals who have never met before, throw in a few man-and-wife couples for good measure, then make them all live within close proximity for a week. It's called a group holiday and there are all manner of interests and subject areas that they cover, from watercolour painting to spring-flower spotting, from scuba diving to hiking.
I have a penchant for the latter and a couple of times a year find myself thrown into the social experiment test tube or behaviourist pressure cooker that is the specialist group holiday.
One of the most common mistakes people make is to assume that there is one rule for them, and another completely different set of rules for everyone else. And so, for instance, when you are on a group holiday you might be tempted to think, "Everyone here is odd – except for me, of course."
The truth is that all the others will be thinking the same – or, in my own case, they might well be thinking, "He's more strange than the rest of us put together."
Group holidays are fascinating in that they reflect our vast society in a tiny microcosm made all the more intense by the isolationist sensation of being in some foreign place where everything is different from one's own snug and homely norm.
Such holidays begin with a general assumption that, because we are all Brits thrown together in a foreign land, we must be all more or less the same. After all, we eat marmalade – a habit that seems to have eluded the rest of humankind.
However, a third of the way in to a group holiday, the cracks begin to appear. The intense heat of the Mediterranean, for example, burns away some of our social niceties. Irritability can become commonplace.
A normally polite and demure woman whacked me over the head with a map because she thought I had jumped the queue waiting to board a bus. I cannot imagine she would do this at home – but then, the sun does not burn down here at 36C.
Somehow you can overlook what is obviously abnormal behaviour – it is the way people are when you see them close up and personal doing what they normally do that you start to shudder with shock. Here is an example of that – a male member of another group holiday sharing the same hotel has a laugh I imagine might sound like a donkey undergoing castration. We are in Menorca and I swear hikers in neighbouring Majorca can hear it 28 miles away.
People creating crazy TV cartoons for kids could not invent such a laugh. It punctuates the air like some insane police siren wheezing its violent last.
It is what this bloke does. It is how he is, how he evolved. Without the services of a spouse who years ago would have told him to put a lid on it. "I don't care how rich and handsome you are – I will leave you if you EVER laugh in that way again."
That is what someone should have said to this poor bloke when he was young. Now it is too late. I can imagine him going to one of those lonely hearts club meetings and scoring a degree of success until... Heee-haaaw, heee-haaaw! I can almost hear the deathly silence that would ensue.
The kind of silence that must reign supreme after you have allowed your ear hair to grow unabated for 70 years. If there is anything worse than that, it is telling someone all about it over dinner.
But if there is no Mrs McTavish to say: "Shut up Jock – no-one wants to hear about your ear-wax problems", how would Jock know?
I am lucky – I have got a highly critical wife who is more than happy to kick me under the table. Goodness knows what faux-pas and other social horrors I would commit without the occasional bruise on the shin or without hearing my name uttered urgently under her breath in the same way she might whisper the name of a poisonous snake.
My theory is that, just under the thin veneer, we are all mad – it is just that some are trained or conditioned to hide it better than others.