Bad internet. Naughty internet.

During a break in rehearsals (www.jumpthemusical, you know you want to) yesterday, I embarked on my customary five minute tour of internet inspection. It goes something like this: email,to find out who's been spamming me and to receive countless facebook notifications; facebook, to re-read the notifications my email has just shown me; and then, just for the hell of it, twitter.

Yesterday two names seemed to appear more often than is usual. One, you will probably be unsurprised to hear, was Clare Balding. The other, less predictably, was Gethin Jones. Let's take the latter first.

Initially I wondered why several tweets on my feed seemed to be making reference to the easy-on-the-eye, otherwise uncontroversial Blue Petering health-shop pusher. You might be, too- it was, as it turned out, a minor twitstorm- but it illustrated rather perfectly how the flawless wonder that is the internet can sometimes be so depressingly abused by the flawed wonder that is people.

Here's how the mini-kerfuffle happened. Someone tweeted that Jones was 'no Alastair Stewart', a reference to the former presenter of a programme he now fronts. Jones was somehow made aware of this- perhaps he searched his own name, perhaps someone told him about the tweet- and decided to reply. His reply was 'No shit, sherlock. YOU get the degree for stating the obvious, well done "numbnuts"'

As a reply it isn't Wildean, and I'm bothered by the inverted commas, but it seems like a fairly commonplace exchange. Someone unfavourably compared Jones to his predecessor, Jones responded with mild irritation.

But in doing so he broke one of the internet's most unpleasant unwritten rules. The potshots, you see, only work one way. His flash of anodyne annoyance became a 'hissy fit'. People started tweeting him to say how 'pathetic','Z list' or 'self important' he was, or to affect to mistake him for Steve Jones of T4. In other words, an unremarkable exchange between two people who annoyed each other became, for some, an excuse to hurl abuse at a man who had dared to commit the double offence of (a) being on television and (b) responding in kind to someone who had slagged him off.

People who aren't in the public eye- 'real' people, if we're being tabloidy about it- get to stand behind a wall and say BUM to whoever they like. But if anyone even a smidge famous says 'Don't you say BUM to me! Bum YOU, more like!' that is a pathetic 'hissy fit'. I'm fairly sure, by which I mean certain, that there's a stinking double standard going on there.

I think it would have been wiser of Jones not to reply, and nobody ever claimed the moral high ground with the word 'numbnuts'. But I also think it was understandable- human- that he did reply. And the pearl-clutching over the fact that he may have found the tweet through 'self-searching' is particularly, hypocritically, daft. Have you never put your name into google? I know I have, and so has pretty much everyone I know. Twitter, of course, has a link to search for '@' replies so people can see what tweeters they don't follow have said to or about them. It's human nature occasionally to get curious about what might be being said about oneself, and it doesn't make Jones a preening idiot for wanting to know.

The way twitter reacts to behaviour its users consider unacceptable is now an established social media phenomenon. Stories such as AA Gill's vile playground sneering at Clare Balding (see, you thought I'd forgotten), the man who was prosecuted for making a terrorism joke on the site, the horrid article in the Express about the survivors of Dunblane or (ahem) Jan Moir on Stephen Gately, develop a momentum of their own and quickly reach a tipping point (or twipping point, as someone will doubtless one day christen it). As a way of gently reminding more established forms of media that we won't necessarily accept what we might be fed, it's invaluable. It would be a shame if that precious right-to-reply were allowed to degenerate into throwing random snowballs at people, and running to teacher when they throw one back.