The Learning and Skills Council launched its abortive high court bid last week to outlaw a strike by its staff without getting the go-ahead from government lawyers.
The cabinet office and the Department for Education and Skills had made clear that they would not support the action and the quango would have to follow its own legal advice, an LSC spokesman said.
In the event, a judge rejected the LSC's argument that it would be unlawful for its employees to join last Friday's national strike by the Public and Commercial Services Union (PCS) in response to cuts in public-service jobs announced by the chancellor, Gordon Brown, in July.
The union said that the LSC's "belligerence" had backfired because it angered more of its staff into joining the one-day action.
It reckoned the quango, which was ordered to pay its costs for the three-hour court appearance, would end up with a bill in excess of £20,000.
Barry Sheerman, the Labour chair of the Commons education and skills select committee, said: "I shall be asking some sharp questions about whether it was a good use of public money."
The LSC remains convinced that it acted correctly in seeking an injunction against the 1,700 PCS members among its 4,000 staff.
"Although the PCS has said this was a one-day strike, its general secretary, Mark Serwotka, has been saying that this is the start of the campaign," said David Russell, the quango's director of corporate services.
"We support the learning of over 6 million learners. We won't claim that this would bring our organisation to a grinding halt, but it would be a huge inconvenience."
The union declared that support had been solid from LSC employees for its nationwide action, particularly in London, the north-west and Yorkshire, and said there had been a 12-strong picket outside the Coventry headquarters.
"There's no doubt about it that the LSC's botched attempt to stop the strike resulted in a much bigger turnout for us," said Ruth Serwotka, the union's group president for the LSC, and wife of its general secretary.
According to Russell, 277 staff from the LSC's head office and across its 47 local branches responded to the strike. "That's 16% of PCS members at the LSC and about 5% of our total staff - it looks like a total flop as far as the union is concerned," he said.
He rejected the suggestion that the injunction bid had prompted a greater number to join the action. "I don't think it would have made any difference. We're talking about a core active union membership."
The PCS called the one-day strike for members in the civil service and other public-sector bodies in response to Gordon Brown's announcement of 104,500 job cuts and other anticipated changes to terms and conditions.
The LSC was arguing that it was a "statutory corporation" and not part of the civil service, Russell said.
It was not among the organisations listed in the chancellor's 2004 spending review as having to cut staff, he said. "There were no non-departmental bodies listed there." Nor did the LSC have any plans for staff reductions, having just completed a major "reshaping" exercise in which 800 posts had gone.
The union was wrongly trying to treat the whole of the public sector as one employer, Harrison said. The LSC approached the government, initially hoping that it would help.
"Their line to us was: you are a separate employer, you must take your own legal advice," he said. "Our legal advice was that because we didn't have a trade dispute with the union, any action would be secondary and unlawful."
Mark Serwotka said the soundness of the union's action was confirmed. "However, you have to question the motives and timing of the senior management in the LSC when senior managers in other government departments and agencies have not raised any problems with the strike ballot.
"Unfortunately," Serwotka said, "it highlights the belligerence of the LSC's approach to industrial relations, which would make some of the worst employers blanche."
