A year ago, Seb James and Sir Charles Dunstone unveiled details of the proposed merger of electricals giant Dixons and Carphone Warehouse.

A year ago, Seb James and Sir Charles Dunstone chose London’s landmark Shard as the venue to unveil details of the proposed merger of Dixons and Carphone Warehouse.

If the skyscraper was selected to reflect the height of their ambitions, then this week’s first full-year update was suitably soaraway.

Knock-out like-for-like growth in the core UK business, market share gains and profits likely to beat expectations are all testament to Dixons Carphone coming good on its merger promise.

The retailer has benefited from some one-offs, most notably the demise of former competitor Phones 4u.

But the underlying reasons for its present success hold lessons for other retailers.

Dixons Carphone was built on a vision – the opportunity to be the consumer’s first port of call in a world increasingly adopting and dependent upon often digital technology, especially mobile. The retailer has a sense of purpose.

Crucially, that vision has been acted upon throughout the business, building on Carphone’s strengths and the reinvention of Dixons over several years.

Whether it’s willingness to take on pure-play retailers on price, the remodelling of stores to make them a competitive advantage rather than a disadvantage or investment in multichannel fulfilment and service, the retailer has not stood still.

Even in Greece, battered by political and economic turmoil, there was a spark. Ideas implemented there are even being exported to other parts of Dixons Carphone.

Lofty strategic goals have not been allowed, as is sometimes the case in business, to degenerate into the sort of cliché that appears on corporate websites but not in-store.

As James put it, progress made reflects “a willingness to roll up sleeves and get stuck in”.

That seems to be happening at both constituents of the merged business as integration goes on, and it’s vital.

It doesn’t take long to think of examples of deals that looked good on paper that were undermined by cultural differences and mutual suspicion – think Morrisons and Safeway in the early days.

Dixons Carphone’s performance was in glaring contrast to that of rival Ao.com. It floated last year on a valuation so stratospheric that the summit of the Shard would be a near-invisible pinprick below, but has since disappointed.

The typically ebullient James was confident of more success to come but emphasised, rightly, that there is plenty of work to do along the way.

One challenge is likely to be ensuring that, while the business is on such a high, complacency is not allowed to set in.

Ao may seem less of a threat following recent underperformance but its emergence from nowhere is a reminder that nothing in retail can be taken for granted.

But if Dixons Carphone continues in the same vein it will become a casebook study both in the mechanics of successful mergers and customer-centric retail.