Indeed Green could afford to while away the rest of his days on the green baize. The 47-year-old has pocketed a not-so-small fortune from last year's purchase and subsequent break-up of Sears, the retail group whose acquisition he engineered with the backing of the rather more secretive Barclay brothers.
In fact, Green has spent the past few days holed up in Sears' head office, just off Oxford Street. But rather than picking cards or roulette numbers, Green's manic mental energy has been devoted to selecting the biggest bargain among the retail sector's many basket cases. Storehouse, the stricken BhS-to-Mothercare group, has been dismissed as rather too much of a basket case - at least if you take him at his word. Instead it is Marks & Spencer - once the housewives' choice, but lately fallen on hard times - which is coming under Green's acquisitive gaze.
Or so it is thought, for though Green admitted last week that he was interested in bidding for M&S, he maintains that many more hours of analysis await him before he strikes.
"Talk to anyone who works with me," he insists. "I do detailed studies. I don't guess. They'll tell you I'm well re-searched."
It is no wonder that Green has got down to military-style planning before embarking on the most audacious deal of an already audacious career. For many years, his name has been mud among the City bankers whose multi- billion-pound backing he requires to pull off his coup.
The son of property-dealing parents, he entered the north London rag trade in the 1970s without qualifications, despite attending Carmel College, the prestigious Jewish public school in Berkshire. His chequered early career did have its highlights, notably the seven-figure profit he made in 1985 by selling his option over the Jean Jeanie denim company.
That was enough to convince several blue-chip institutions to back his 1988 takeover of a struggling menswear retailer called Amber Day. His other ventures notwithstanding, it is Green's tenure at Amber Day which continues to make several institutions see a red warning light when they consider his latest plans.
Green's first three years were an extended honeymoon as Amber Day's investors benefited from his Midas touch. His relentless self-promotion was tolerated, although with hindsight Green admits he might have behaved differently.
"I delivered profits in 1991 of pounds 10m on turnover of pounds 85m," he recalls. "I made more money than other retailers. But I got on a bit too quickly and I didn't understand the City game."
The culture clash between Green and the City was exposed in 1991 when he embarked on the ambitious takeover of What Everyone Wants, a Scottish discount retailer several times the size of Amber Day. Suddenly, Green was presiding over a rather larger outfit and the Square Mile's latent concern over his methods, manner and associates began to matter.
First there was Tony Berry, who backed Green's acquisition of Amber Day and presided over the collapse of Blue Arrow, the recruitment agency. Another chum, Ted Ball, was subsequently convicted of corruptly accepting commissions from customers of his Landhurst Leasing company. Not that there was any evidence that Green was involved in anything less than pukka, of course.
By the end of 1991, Amber Day shares were in freefall and it was clear that Green could no longer run the company as a personal fiefdom. Non- executive chaperones were brought in, but claimed that the only way to keep abreast of Green's activities was by reading Private Eye. By September 1992 it was time for Amber Day's investors to grasp the nettle. Green, understandably, has a different interpretation of his departure. "If you really want to know, I got moved over because I got too ambitious in getting to the next target," he says.
Despite his protestations, Green and the City were finished. Seven years later, he may reflect that he has done far better than the banks out of the settlement.
First of all there was the pounds 48m he made by selling Olympus, the sportswear chain he bought from Sears, to Sports Division. Then came this year's lucrative break-up of Sears, the retail conglomerate. Significantly, both deals were confined to the private arena. Green may have been catapulted into the realms of the super-rich, but his reputation in the City still remains blackened.
"He's a wheeler-dealer, not a retailer," said one analyst dismissively. "There's no way he could run M&S."
True, Green's break-up of Sears was a clinical attempt to extract value from the ailing retail chain, but he never promised anything else. Rejecting accusations of asset stripping, he points out proudly that he left the dismantled chain with the same 29,000-strong workforce he found.
Nor does he have any illusions about the task in hand at M&S. Making a fast buck is not an option. Instead, Green will embark on a long-term slog to reverse the retailer's ailing fortunes. The Barclay brothers backed the Sears break-up but have no interest in such a prolonged investment, hence the need to find a group of City banks willing to stump up the near- pounds 10bn needed to buy M&S.
"I don't believe anyone will find it easy to make money in retail," Green says. "But I believe my track record shows that I could succeed with a mixture of the City's money and mine, if I do my homework. If somebody presents an opportunity, should it be about the money or the personality?"
The money, he thinks, is what should matter and he emphasises the amount of his own wealth he invests in his ventures - pounds 3m in Amber Day and pounds 20m in Sears.
However, his personality remains an issue. M&S has suffered a dramatic fall from grace and the City's impatience with its management is well known. The question is whether M&S's shareholders are sufficiently fed up to give Green the chance to rescue the reputation of a once-great retailer. That would mean granting him a seat on the board of a listed company for the first time since he ran Amber Day.
And for that to happen, the City will demand some serious salvage work on Green's own good name.