Tom Watson’s reputation for intrigue is sufficiently well-established at Westminster that MPs tend to see double meanings in everything he does. In the summer of 2017, one Labour peer collared me in the corridors of parliament and demanded to know what the party’s deputy leader was hoping to achieve by cutting out sugar and taking up exercise. I explained that he was hoping to lose weight and improve his health. “Ah,” the peer replied, entirely seriously. “So his plan is to wait for Corbyn to die.”

Since the departure of seven Labour MPs to form the Independent Group (TIG) – whose ranks now stand at 11 thanks to an infusion of three Conservatives and the Enfield North MP, Joan Ryan – Watson has become increasingly willing to air his disagreements with Jeremy Corbyn and the party’s strategy in public. He has also set up a new grouping for Labour MPs in parliament to discuss and develop policy.

Even Labour figures who wouldn’t see conspiracy in a diet plan are asking: what is he up to? “There are three options,” one told me. “Is he rallying MPs in order to lead them out of the Labour Party? Is he trying to hold Labour together? Is he out to get rid of Jeremy? Part of Tom’s success is that he can hold all of those possibilities in his mind and not really be sure which one he is working towards.”

Corbyn’s inner circle think they know the answer: Watson wants to get rid of Corbyn. They haven’t forgotten that he tried to persuade the Labour leader to stand down in 2016, and they suspect that Watson was one of the 14 members of the party’s ruling National Executive Committee who voted in favour of Corbyn needing to seek fresh nominations to stand again – a hurdle that he would have been unable to clear. (At 18 to 14, that vote is the closest Corbyn has yet come to defeat in the game of internal Labour politics.)

Animosity to Watson is strongest in the corner of Corbynland that was once most sympathetic to him: those who cut their teeth in Unite, which used to be Watson’s power base. But since his friendship with the union’s general secretary, Len McCluskey, turned sour, Watson and the Unite faction have been enemies. That matters. Unite allies turned Labour staffers include Karie Murphy, Corbyn’s chief of staff, and Jennie Formby, Labour’s general secretary.

Murphy supported a doomed attempt to introduce a second, female deputy leader at last year’s Labour party conference, a grassroots measure designed to further reduce Watson’s power. And Formby recently upbraided Watson for asking Labour MPs to inform him about any complaints they made to party headquarters about anti-Semitism or bullying in the Labour ranks. She publicly copied the message to every Labour MP and peer, essentially guaranteeing that it would leak.

No one seriously disputes that the deputy leader would rather Corbyn was not in post. One ally recently quipped that Corbyn was Watson’s 245th choice in parliament to lead the Labour Party, behind only Fiona Onasanya, the Peterborough MP who was at the time on trial for perverting the course of justice. (She has since lost the Labour whip, after a guilty verdict.) But equally, no one in Labour seriously believes that there is any prospect of dislodging Corbyn. Watson is not mad or foolish enough to think it is a good use of his time to try.

That fact is part of what drove the seven founder members of TIG out of the door and some Labour MPs believe that Watson plans to use his new grouping as a launch pad for another split. Although perhaps “hope” is a better description of what those MPs are feeling. There is a sizeable contingent of Labour MPs who essentially agree with TIG’s critique of Labour’s present leadership, but still have no desire to join the group.

For some, that’s because of a personal animosity to Chuka Umunna, TIG’s de facto leader, or a political objection to the centrist position the new group is setting out. “Chuka says we don’t need Labour 2.0,” one Corbynsceptic Labour MP grumbled to me, “I say: what’s wrong with that?”

Any hopes that Watson will create a more left-wing version of TIG, however, are unfounded. He has worked for Labour for essentially his entire adult life, and like most Labour MPs has an incredible affection for the party. MPs known to be contemplating life outside Labour are invited for tea in his parliamentary offices to dissuade them.

So if a coup is a non-starter and a split is impossible, what is Watson up to? The answer is that he sees his role as that of a shop steward to the parliamentary party and a beacon for the party’s remaining Corbynsceptic members, to avoid the trickle of exits becoming a flood. The aim of his new grouping is in effect to provide a support network and safe space for Labour MPs contemplating life outside the party. He is worried not only by defections to TIG but by MPs emulating Ian Austin, a former ally of Watson’s, who has quit Labour but is not expected to join Umunna’s group because of its aversion to Brexit.

Watson is trying to avoid what his supporters see as a twofold risk. The first is that Labour enters the next election in a state of disintegration. The second is that if Labour gradually loses the bulk of its Corbynsceptic MPs – whether to TIG or simply to life outside the Commons – the result will be a fringe party that cannot win another election.

Can he succeed? Watson’s new “shop steward” approach involves a greater level of belligerence and a greater public focus on the party’s problems. That in turn highlights the dilemma of Corbynsceptic MPs: their only options are to join TIG, or wait for Corbyn’s political death. And by making that choice so obvious, Watson’s attempts to keep worried Labour MPs in the fold may simply hasten their exit.