Well that didn’t take long.

A couple of days ago, this column suggested that next time the supermarkets got flak for being the source of all evil in the world, they could do worse than point to the most recent Grocer Price Index.

The index, the only measure of inflation that takes promotions into account, revealed that Asda and Tesco have both done a pretty good job of keeping a lid on price rises.

Tonight, the UK’s two largest supermarkets will be in the firing line from the BBC’s Watchdog programme. It will accuse the retail giants – currently embroiled in a gloves-off tear-up – of some pretty sharp practice on pricing.

Anne Robinson and pals will claim Asda has put the price of some Rollbacks up, rather than down – rather like how, in George Orwell’s 1984, the rulers of Airstrip One (that’s Britain) announce each reduction in chocolate rations as an increase. Tesco, meanwhile, will apparently be accused of selling ‘value packs’ that are pricier than when the items concerned are sold separately.

Clearly it’s not possible to say much about the claims before they’ve been broadcast – and before the retailers involved have had their say in response. But coming after the second ‘Black Wednesday’ – when petrol prices hit yet another new high despite the Chancellor having cut duty on fuel – the GPI is pretty strong evidence that all those promotions aren’t simply there to confuse the punters.

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