Today is Blue Monday. That’s the most depressing day of the year, if you believe ‘research’ paid for by online travel agents that want you to book some winter sun.

Perhaps that explains the tetchiness in the weekend’s exchanges between Tesco and Asda over the latter’s 10% pledge.

Although The Grocer’s editor, Adam Leyland, noted in Saturday’s leader that the uptake from customers is currently more of a trickle than a flood, the extended Price Guarantee has certainly ruffled feathers in Cheshunt.

Richard Brasher, who’s becoming an increasingly ubiquitous media presence as the date nears of his ascension to UK chief executive, had some pretty robust views about what he called “false Asda claims”.

“It is vitally important the whole industry acts in a way that deserves the trust of customers,” he said. “We are calling on the Advertising Standards Authority to act – and act quickly – because in our view customers are being misled.”

These days, supermarkets complain about each other to the ASA with the ill-tempered regularity of playground tell-tales, bemoaning alleged sharp practice over sometimes-esoteric discrepancies in price comparisons and advert ‘basket sizes’.

On the other hand, Tesco has said it will redeem the vouchers Asda is giving out to make up the 10% saving it guarantees on 15,000 items.

The hardening of criticism in the past few days is surely a sign that the 10% claim is being taken increasingly seriously. That’s one reason for Asda to be cheerful on this otherwise gloomy Monday.

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