The behaviour of Geoff Hoon and Patricia Hewitt is a fine example of how not to lead a plot. Both have been making the media rounds claiming, absurdly, that their decision to call for a secret ballot on Brown's leadership is not designed to undermine the Prime Minister. Do they really believe that Brown could emerge strengthened from a disruptive ballot? Their refusal to declare which way they would vote is taking the PLP for a bunch of fools.
There are several reasons why this plot is likely to fail. First, the decision to go public strongly suggests they have failed to persuade any cabinet minister to turn against Brown. While the Prime Minister retains the support of cabinet heavweights such as Mandelson, Miliband, Darling and Straw he is likely to survive.
Second, that this latest plot is led by two unambiguous Blairites means the centre left of the party, focused around the Compass group, is unlikely to join in. So long as the rebellion remains confined to the usual suspects -- Charles Clarke, Frank Field, Barry Sheerman -- Brown and his allies can dismiss this as another botched coup.
Third, there remains no pre-eminent, Heseltine-style challenger for disaffected MPs to coalesce around. It is noteworthy that neither Hewitt nor Hoon named an alternative leader.
Finally, as my colleague James Macintyre, who broke the story today , has pointed out, their plot comes after an unusually strong performance by Brown at PMQs, something that is likely to have lifted the mood of backbenchers.
Although he is likely to survive, the latest plot remains a disastrous development for Brown. The Tories and the Lib Dems will declare again and again (and they'll be right) that Labour is a divided party and that the electorate hates divided parties.
The psephological case against Brown remains strong. No prime minister has been as unpopular as him and gone on to win the subsequent election. But at this stage it's hard to see how a prolonged and bitter leadership contest could be anything but damaging for Labour. Should the party wish to avoid a catastrophic defeat at the election it must call time on this pitiful spectacle.