But when the dust settled, both his job as chief executive and his pounds 475,000 pay packet were intact. Thanks to the votes of the big institutional shareholders - pension funds and insurance companies - Brown and the rest of the British Gas board left the podium bloody but unbowed, and confident that the nightmare was over.
Four months later, however, the company is facing a much greater threat than the raspberries of 4,500 angry private shareholders. The furore then was about a single salary payment that could not make a flea-bite's difference to a company the size of British Gas. The worry now is about events that threaten to wipe billions of pounds from the company's revenues.
Institutions which then backed Brown and his chairman, Sir Richard Giordano, are beginning to wonder whether their loyalty was misplaced. The doubts have already hit the share price. The shares on that infamous afternoon were trading at 305p. They are now worth just 258.5p after a 6.5p fall on Friday - their lowest this year. Shareholders have seen pounds 2bn wiped from the value of their portfolios since the AGM. The shares are now worth little more than before the stock market crash of 1987. Compared with other privatised utilities, British Gas has delivered a decidedly pedestrian return. This is more than academic for the 1.8 million "Sids" who subscribed for the shares in 1986 and remain shareholders to this day.
Some institutional investors recall how Giordano justified Brown's controversial pay rise by insisting that management performance had to be paid for. Yet in terms of short-term share price movement at least, Brown has done anything but perform. "Much of the discussion on directors remuneration before the AGM covered this very issue," commented one leading institutional investor.
The City is not yet demanding Brown's head on a platter. But there are few voices to be heard in support of him. It is significant that the recent round of presentations to big investors was handled by Roy Gardner, the finance director, sometimes with Giordano, sometimes without. Brown was nowhere to be seen.
Gardner, a former managing director of GEC-Marconi, seems to be universally admired by the fund managers. There are some who would like him to step into Brown's shoes sooner rather than later. He has one key advantage: having only arrived at the company in November 1994, he cannot be blamed for past decisions that are now coming back to haunt the company.
The most catastrophic of these was the decision over the last decade and more to enter into long-term contracts with oil companies for the supply of gas from the North Sea. While the current or "spot" price for gas has plunged to around 9-10p a therm, British Gas is locked into contracts under which it is paying more than 20p a therm.
The impact has been disastrous and will continue to be so. Rivals supplying industrial and commercial customers - the part of the industry opened up to competition - are able to buy their supplies for much less and so undercut British Gas. Under these crippling "take-or-pay" contracts, British Gas need not take the gas, but it still has to pay for it.
Paul Spedding, a gas industry analyst with Kleinwort Benson, reckons that the company will this year be forced to pay as much as pounds 700m for gas that it does not need, pounds 300m in 1996, and pounds 200m-pounds 300m in 1997. "It's a pounds 1.3bn headache. That's the value of the gas they're going to have to buy over the next three years and have no home for."
It is a horrifying prospect, even for a company making profits of pounds 1bn a year. It hopes to renegotiate the contracts with suppliers, but the counter-parties, oil giants such as BP and Shell, have absolutely no incentive to rewrite perfectly legal and binding arrangements just to suit British Gas, especially as it would lose them money. Analysts say there is little hope that the company will escape its painful obligations.
Once the Interconnector pipe from Bacton in Norfolk to Zeebrugge in Belgium opens in 1998, the company may find a Continental home for its excess gas.
But even here, the prospects are considerably dulled, because both the Russians and the Norwegians are also trying to dump surplus gas. British Gas could shut down its own production, for example from its platforms in Morecambe Bay, but that has its own associated costs.
The only realistic hope is for a cold spell that gets the entire country turning up the heating a notch. Spedding at Kleinwort Benson reckons a really vicious winter could wipe out one-third of the problem. But the alternative - another mild winter - would add to the problem.
So who is to blame for this fiasco? Not us, says British Gas. It stresses that it signed the contracts before it realised how much the Government was planning to open up the gas market to competition. When it began
signing these contracts before privatisation in 1986, it had a 100 per cent monopoly and a statutory duty to supply everyone. It was, it claims, perfectly logical to lock in to long-term supplies.
The City has largely accepted this explanation. According to one institutional investor: "I don't think any other management would have done any differently, quite honestly." Brown and his colleagues were blameless, they think.
The reality is rather less black and white - 45 per cent of these damaging contracts were signed after privatisation in 1986, by which time the Government had spelt out how it wanted to see competition in supplies to industrial and commercial customers. The company continued to sign contracts for the next eight years, despite reform after reform to introduce more competition into the industry. It was still locking itself into these contracts in December 1993, when Michael Heseltine, then President of the Board of Trade, announced that the domestic market would also be opened up to competition. Even then, it carried on, signing a final long-term deal in the spring of 1994.
According to one rival gas company, British Gas ignored the evidence of its eyes and continued committing itself to future purchases. "The writing was on the wall long before they stopped signing those contracts."
If the "bubble" of excess gas is the most pressing of the company's problems, it is far from being the only one. Another big threat is looming in the shape of a review of the pricing regime for its transportation and storage business TransCo. This is the pipeline business that transports gas from the coast to the cooker or boiler. It remains a cast-iron monopoly and has been the company's cash cow. In the last six months, it contributed no less than pounds 745m to the group's pounds 994m of operating profits.
But Clare Spottiswoode, the director-general of Ofgas, is threatening to alter that. She is roughing out a new pricing regime for TransCo which, according to Daniel Martin at stockbroker BZW could significantly dent profits. His best bet for the new formula would have wiped pounds 1bn from TransCo's revenues if it had been in operation between 1993/94 and 1996/97. Martin believes a tough new formula for TransCo could force the company to cut the dividend.
TransCo has done little to win friends at Ofgas or among its new customers - independent suppliers such as Mobil, Kinetica (a joint venture between PowerGen and Conoco) and Alliance Gas (BP, Statoil and Norsk Hydro). It recently agreed to pay pounds 11m in compensation to independent suppliers because of delays in meter-reading and other problems.
Worse was to come when, two weeks ago, it announced a 10 per cent increase in transport charges from 1 December. "They made no attempt to consult us or explain the rise," said one disgruntled supplier. "They've lost any goodwill they might have had. That has to backfire on them when the regulator comes to look at the pricing formula."
Other episodes have also led investors to question the quality of the British Gas management. Their worry is that the company's lamentable handling of Brown's pay rise was not a one-off, but a reflection of poor judgement in the boardroom.
The company's continuing problem with customer complaints raises other questionmarks. Last week, the Gas Con- sumers' Council revealed that complaints so far this year have doubled to 30,000. Nine thousand families were left at some stage with no hot water, no gas to cook with and no central heating, the GCC report said.
Ian Powe, the GCC's director, said the company had sacked too many staff and subsequently had to take on temps who were not so well trained. "To change the culture of a company like British Gas, and to try to do it with the same people - but just fewer of them - is a recipe for staff and customer discontent, as events have proved."
The spectre looming over all else is the introduction of competition into domestic supplies. From 1998, all 18 million of the company's domestic customers will be able to buy their gas elsewhere. A pilot scheme begins next April in the south-west.
The immediate outlook is gloomy and analysts see no likelihood of any bounce in the shares. Some investors bailed out before the recent share price weakness. Robert Fleming, the fund managment group, sold its entire 3 per cent holding last year.
The company itself continues to blame factors outside its control for its problems - the Government, the weather, the regul- ator, the media. Shareholders are beginning to wonder whether at least some of the fault lies closer to home. The company is repeatedly forced to deny rumours that Brown is about to leave. He turned 60 earlier this year, but the normal retirement age is 65.
Even the cast-iron reputation of Giordano has taken a pounding. It was only a year ago that he hired the Queen Elizabeth II Centre opposite the Houses of Parliament to unveil his bold new vision for British Gas. That vision looks distinctly tarnished.
Some gas watchers say Brown would be the last person to go because he is "Giordano's lightning conductor". Any problems can be placed at Brown's door. That, in the end, may be what saves him - and the embarrassment of having to pay out the pounds 950,000 severance fee to which Brown would be entitled under his two-year rolling contract.