No such thing as bad publicity?

Apparently retailers are sensitive to a thing called "the Delia effect": ie, if a product is featured on Delia Smith's TV programmes, it will start to fly off the shelves. I can well believe it, but I think that, if anything, it underestimates the value of publicity. If you cast your minds back to last week's story about John Prescott's bulimia, you might remember that his confessions included the following line.

I could sup a whole tin of Carnation condensed milk, just for the taste, stupid things like that. Marks & Spencer trifles, I still love them, one of my favourites. I can eat them for ever.

I was in a Marks & Spencer store over the weekend and couldn't help but look out for their trifles. They were on special offer and had nearly sold out. (I bought the last carton of three individual trifles, naturally. As pre-prepared puddings go, they're not bad). Can we now talk of a "Prescott effect" hitting the grocery market?

If only I'd thought to check on sales of Carnation condensed milk, that might have sealed it.