Jim Armitage: Sainsbury's boss Mike Coupe's 'courageous' Home Retail Group tie-up needs to be backed up by numbers

If you thought the opposition to Sainsbury’s plans to buy Home Retail Group would dent Mike Coupe’s ardour, think again.

Today saw him and his team doing a hard sell for his — ahem — courageous idea.

So enthused are they that they’ve issued a 21-page brochure selling the benefits.

This covered familiar ground: the advantages of sticking Argos concessions into spare Sainsbury’s shop space and the hope that customers will spend more through the combination of shops, click-and-collect and online.

But more important was that management at least acknowledged concerns about the disruption such a deal would cause them at a time they need primarily to fight Aldi and Lidl.

Don’t panic, we were told: the cultures are similar, and many staff have worked in both companies. It could be worse.

But there remain no details on price, cost savings and synergies.

Until we know more about that, it’s impossible to gauge whether this deal makes sense. So, come on, Mike. Show us some numbers.