Which is why the Tories are getting all excited about David Cameron's more or less spotaneous performance in Lewisham last week. It's proof, they say, that all those Cameron Direct events have paid off; that Dave can think on his feet and connect with ordinary folk. Which may well be true. But there's a danger that the Tories could start crowing about it too much. I mean, look at the quotes a "senior Tory strategist" gives to the Guardian's Nick Watt today: "Authenticity is key to this election," they say, "that is why we are so confident. People sniff you out." And another adds, for the sake of clarification: "Gordon Brown is not capable of doing these open meetings".
Ok, so those quotes aren't terrible. But the Tories should be aware that the more they talk about authenticity – the more they appear to present it as a hard strategic choice – the more, erm, inauthentic they risk looking. In the end, "show, don't tell" is as good a maxim here as anywhere.