But when his typically sure footing did slip, as it did after the takeover of Safeway, when the business was sent hurtling off a cliff. The disastrous aftermath effectively broke Sir Ken's iron grip on the grocer, culminating yesterday in the much-anticipated appointment of Marc Bolland as chief executive.
Since Bolland hasn't started yet and hasn't had the chance to make an impact, it might seem a bit churlish to question his credentials - but here goes.
Was there really no suitable candidate with the right sort of retail track record who could be convinced to take the job? Bolland has spent most of career at Heineken - a consumer goods giant certainly, but a different beast from a stores empire in the UK's most competitive retail sector.
His hiring was greeted with surprise - even consternation - in some City circles, where the hope had been that a top-flight shopkeeper would be drafted in to deliver an M&S-style recovery.
There were reportedly some big names in the frame -Tesco's Colin Holmes, WHSmith's Kate Swann, even Asda saviour Archie Norman. And those are the sort of names that the City and the retail sector would really have liked to hear confirmed in post at Morrisons.
The upshot is that Bolland will come in for pretty fierce scrutiny, putting him under extra pressure as he strives to improve the retailer. Don't be surprised if there are mutters that Sir Ken wasn't so bad after all - better the devil you know and all that.
Bolland deserves support, if for no other reason than he's the only show in town, but he will have a lot to prove.
Secretive tycoon Mike Ashley is likely to be one of the retail winners of the World Cup.
Outside sports retail, Ashley was unknown until a few years ago. But he's come up the field as fast as Theo Walcott and we report this week another acquisition - this time of Original Shoe Company - as well as the launch of a transactional Sports World web site.
The online venture in particular is likely to worry JJB Sports. Ashley has already put a few into JJB's net as a result of his ferocious discounting. Now he is taking it on in cyberspace, hard on the heels of JJB's own launch of an e-tail site.
With an empire spanning the range from brands such as Donnay, the core Sports World chain and Piccadilly's famous Lillywhites, Ashley has become one of the most powerful people in retail today.
His£11.99 England shirts are likely to have kept his shops busy in the run-up to the World Cup, but his growing influence is likely to carry on being felt long after the final whistle.