Speaking about his London Marathon exploits, the business supremo regaled the audience with the story of how his friends at Cadbury suggested sponsoring him.
Spotting an opportunity to have the brand seen by thousands of spectators, marketing chiefs went the whole hog by rustling up a T-shirt for Jones adorned with the Cadbury logo.
The portly Jones then thought it would be funny if he wrote on the back of it 'Chocolate is good for you'.
However, as PR execs caught whiff of an another 'Cadbury does sport' gaffe, the marketing department got the collywobbles.
Digby told the conference: 'I got a phone call from a worried marketer saying: "We've thought about this and don't think it would look good if you died." I told them there was no way I was going to change it, and after a delay got another call saying: "OK, if you do collapse, can you make sure you fall on your back so spectators can't see the writing?"'
Admirable contingency planning from the confectioner, but Jones made it over the line in five hours and 58 minutes - and lived to tell the tale.