"(Jack Train) created Colonel Chinstrap, a pickled former Indian Army officer who perpetually believed he was being offered a drink, replying: "I don't mind if I do". Chinstrap was based on a real person. Train was visiting the BBC's chief announcer, John Snagge, when in came a bleary-eyed former army man, another friend of Snagge's.

The arrival said: "John, I've just done the most marvelous piece of business. I've bought a water heater on 10 years' hire purchase and what the gas company don't know is that I am drinking myself to death."

When the man heard the show he failed to recognize himself but commented: "Wonderful character. I knew silly buggers like that in India." And then, nine years and five months after the first meeting, Snagge sent Train a telegram: 

THE COLONEL BEAT THE GAS COMPANY BY SEVEN MONTHS."

 

-From the Wikipedia article on wartime radio comedy 'It's That Man Again'.