Now he sits in his aquamarine office at Thames, counting the days until the company's Tower Bridge logo vanishes below the murky waters of its namesake river for ever. On 31 December Thames ceases to be London's weekday ITV contractor, continuing instead as an independent production and distribution company.
Mr Elstein makes a valiant show of not seeming too downhearted. 'I've been to one network scheduling meeting in the past three months because they're talking about the future and I'm not part of that,' he says. 'The lack of meetings is the more pleasant side, actually. A huge bonus.'
But friends agree that, despite his accustomed cool exterior, Mr Elstein was devastated by the loss of the Thames contract. Even while delivering his MacTaggart Memorial Lecture at Edinburgh last year, he knew his company had been massively outbid by Michael Green's Carlton TV. But he still believed the Independent Television Commission would invoke the 'exceptional circumstances' clause in the Broadcasting Act, saving Thames on the basis of its past record. Only afterwards did he realise that 'the exceptionality clause wasn't worth the paper it was written on'.
'The worst thing is not the effect on me personally,' he says. 'It's being faced with hundreds and hundreds of people who are about to lose their jobs because of a decision over which they have no control, and where you have been forced by legislation to choose between risking those jobs or keeping the company profitable.
'It's very, very upsetting for the ITC to have made a decision that leaves Thames profitable but puts perhaps 1,400 people out of work. They are the true victims.'
Many of the Thames staff were aggrieved that their board did not put in a higher bid for the contract. To do so, Mr Elstein says, would have tipped the economic balance of the company so far askew that most of them would have lost their jobs anyway. 'In many ways, the system was set up so that publisher-contractors could dislodge producer-contractors. Thames could have taken the view that it should get rid of all its staff ahead of time and bid higher. But that was no comfort - it just meant everyone losing their jobs in 1991 rather than 1992.'
Well dressed and quietly spoken, Mr Elstein, 47, belongs to a vanishing breed of senior ITV figures dedicated to the ideal of public service broadcasting. In his MacTaggart lecture, he spoke bitterly against the Thatcher government's willingness to throw independent television to the commercial wolf pack. The 10 months since the auction free-for-all have not dimmed his anger and resentment.
Many in the industry still believe that the government targeted Thames to lose its franchise. It had, after all, made Margaret Thatcher furious by screening Death on the Rock, the documentary which suggested that IRA suspects may have been illegally gunned down by British agents in Gibraltar.
Mr Elstein wryly contrasts his treatment as loser with that of TV-am's Bruce Gyngell. 'It was significant that Mrs Thatcher did not send Richard Dunn (Thames's chief executive) a telegram saying: 'We never intended you to lose your franchise.'
'This is the first time we've had a government so willing to take on its perceived enemies.'
Ironically, no sooner was Thames's death sentence pronounced than it enjoyed a critical hit. The three-part adaptation of Angus Wilson's Anglo-Saxon Attitudes was hailed as a return to the great days of ITV drama and is a favourite for next year's Bafta awards.
Mr Elstein doubts that ITV viewers will look upon its like again. Though hugely successful for a 'literary' drama series, its audience of eight million fell short of the 10 million that Thames's successor, Carlton, promises to deliver in peak times.
He has some sympathy for the new licencees, by implication even for the company that has replaced his own. 'How can you put people under such financial pressure and then expect them to deliver innovative drama and current affairs in peak time?' he asks. 'The days when quality ruled the roost have gone.
'Television has become more routine, less of an event; it's more neurotic, less stimulating. There will be more episodes of known popular programmes, fewer new programmes, fewer risks taken and fewer failures. The shift is inevitable, because ITV has been forced into a more commercial posture. And the audience may prefer it, for all I know.
'Maybe the future will offer viewers greater opportunity to exercise choice, even if that choice is quite narrow. The television of the past was geared to my own tastes, but perhaps the television of the future will suit the general public more. In the past, television was tilted towards the educated elite. Maybe it's right and proper that the population at large should exercise their buying power.'
The slim-line Thames barely ranks as a tributary, with its staff of 160 as opposed to the former 1,500. But in its new role as production company, the future looks solid enough. Mr Elstein has negotiated a pounds 29m production deal with ITV for next year, to continue making Thames classics such as The Bill, Wish You Were Here, This is Your Life, Minder, and Rumpole of the Bailey. There are plans to launch a satellite channel in partnership with the BBC, showing material from their combined huge archives.
Thames may even still have a future as a network, being the sole remaining bidder for the new Channel 5. But if it wanted more than a 20 per cent shareholding in either the new terrestrial or satellite channel, it would have to give up its independent producer status.
After years of feudal power as an old-style programme controller, will Mr Elstein be able to settle back into the life of a mere independent producer? His name has been mentioned, along with that of Charles Denton of Zenith and Granada's Steve Morrison, for the key new job of ITV central scheduler.
He is quick to pour cold water on the speculation. 'No one's offered me the job and I don't expect them to, even though I'm obviously qualified for it,' he says. 'I'd be too much of an outsider.'
He is believed to be committed to staying with Thames until the company's new character is established, which could take until the middle of next year. Afterwards, retirement from television altogether is an option. But ITV can ill afford to lose a thinker of such stature.
In his MacTaggart Lecture last year, Mr Elstein called on broadcasters to define what they valued in television and fight for those values before it was too late. A year on, he sees no sign of such a debate getting under way. 'The industry is obsessed by survival,' he says. 'When you are worried about the BBC Charter and the economics of ITV or independent production, the philosophy of broadcasting doesn't loom large in the consciousness, I'm afraid.'