You go to a formal dinner party. You talk to the person on one side during the starter, the other during the main course. Sometimes the conversation skips along, more often it drags and falters. You enjoy or endure the evening, and then you go home.

That is, unless you are Mr Robert Hiscox. The founder of the eponymous insurance company told me some years ago that at the end of a dinner party, he turned to the people on either side and offered feedback on how he had found their conversation. He would say: "I enjoyed hearing your views on the European Union, but you might have asked me about mine." Or: "It was interesting to learn about how well your child did in his A levels, but you seemed reluctant to discuss other topics."

At the time, I was shocked. How could he be so rude? Mr Hiscox assured me that conversing at formal dinners is a skill; it is hard to get better at anything if no one tells you where you are going wrong. I protested that there was far too much feedback in the world anyway. Sometimes it was nice to be left alone to muddle through.

Two things have made me change my mind. The first is that in the years since then, I have been to too many dinners and sat next to too many people who were not trying hard enough. The second is the realisation that although there is too much useless general feedback (no, I don't want to rate my experience in security at Heathrow Terminal 5), there is almost no specific feedback that helps us to improve.

Not long ago, I got an e-mail from a man who had been in the audience of a speech I had just given. "You really need to sort that hair/reading glasses challenge," he wrote. "Every time you put your reading glasses on, your hair falls over your left eye and you then keep having to flick it out of the way - it looks most amusing, but must be awkward!! As a regular presenter, I always like to get feedback. Hope you don't mind me pointing it out!"

I did mind his pointing it out. Unlike him, I never like to get feedback, unless it is entirely positive. And in any case, how dare he? I never asked for his views. And if he thought a few exclamation marks would make his message more agreeable, he was making a grave error.

Yet his words struck home. It was not nice to think the audience's merriment had been mainly on account of my hair. So for the next few speeches, I printed out any notes in 24 points so I could read them without glasses, and have now cut my hair so short there is no further danger of flicking.

On reflection, this man's feedback was close to perfection. It was direct but not rude. It was clear about what was wrong - which was something fixable. It came from a disinterested source and was delivered by e-mail - so it saved my blushes.

Last week, another piece of unsolicited feedback landed in my inbox. This time it was from someone who was thanking me for talking at a conference he had organised. After a gracious start, the e-mail finished like this: "I always try to end with a tip for improvement. It was a little complicated to get in touch, confirm your travel plans and do the arrangements. Can I suggest you get an assistant?"

This was also good in that it was clear - only rather harder to fix than the hair as assistants do not come cheap. Still, it told me that my habit of ignoring administrative e-mails is not on. I have heeded the point and will try to sharpen up.

The test of unsolicited feedback is not whether it is rude or unwelcome, but whether it serves the greater good. I no longer flick my hair and am committed to replying more promptly: The world is a happier place.

Soon after my lunch with Mr Hiscox, I was seated at a dinner next to a well-known snooty broadcaster. Throughout the meal, I tried hard to be agreeable; he sat there taciturn, looking catatonic and mildly incredulous as I plied him with questions and anecdotes.

At the end of the evening, I longed to offer him a report card, but bottled out. I have regretted it ever since. I bet that if I had explained his poor performance, he would have been first shocked, then mortified. I dare say he would have liked me (even) less, but might have tried harder in future. Next time, I'm going for it.

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