Labour must focus on opponents, not on tearing each other to bits.
Political pundits are predicting a bloodbath if David Cunliffe is elected Labour's leader tomorrow and fails to quickly unify the caucus.
If Grant Robertson triumphs, he is likely to face a smoother path. He is an affable player.
The edges - such as they are - were burnished off years ago. Robertson has mastered the art of slipping between the factions. But he is still developing a killer instinct.
Cunliffe is reputed to have greater support in the party at large. He would, of course, have to accept the hand caucus deals him when it comes to the deputy leadership.
There is considerable room for doubt over whether Cunliffe really embraces socialism. Or whether it is just convenient window-dressing to boost support in the Labour Party at large to make up for the considerable distrust he faces within the caucus.
He is still not prepared to live among the masses, preferring Herne Bay's salubrious environs to shifting house to his New Lynn electorate.
His "pork-fest" campaign where he pledged to spray cash about to underwrite inane vote-buying policies did not befit someone who has held the shadow finance portfolio and might again if Robertson wins.
That said, there is room to exercise considerable patronage through astutely awarding pivotal shadow portfolios and ensuring a front bench that is, in the words of the late David Lange, "surging in debate and active in the cause".
The brute reality is that Labour's leading lights - including the three leadership contenders Robertson, Cunliffe and Shane Jones, together with experienced political pros like Annette King, Phil Goff, Lianne Dalziel (whom Shearer ridiculously relegated to the back benches) and Trevor Mallard - have not been firing on all cylinders in Parliament.
In the past year they have given the impression they held back and pulled their punches to ensure they did not publicly outshine Shearer. As indeed any of them could without breaking into a sweat.
The upshot is that Green Party co-leader Russel Norman has comprehensively filled the leadership vacuum on the Opposition side.
Other MPs like much-touted future leader Jacinda Ardern have been pole-vaulted on to the front bench only to be made mincemeat by National's Paula Bennett.
It is fatuous to talk of Ardern taking on a senior Labour role given her inability to wage political war in the debating chamber. But she will nevertheless be a strong contender for the deputy leadership.
There is plenty of newish talent including Phil Twyford, David Clark and of course Shearer himself - who was not politically blooded before being catapulted into the leadership - which could be usefully deployed.
But for the new leader to get his team performing, he has to perform what Jim Bolger used to refer to as "horizontal management" to focus the competing egos and energies on their opponents and not on tearing each other to pieces. That's not an easy task as Bolger found out when he was later rolled by Jenny Shipley after caucus colleagues felt his man management skills did not extend to keeping National's coalition partner, NZ First's Winston Peters, in line.
There has been much speculation that the incoming leader - particularly if it is Cunliffe - will very soon find himself being undermined by caucus opponents.
This is being deliberately fanned, not just by Cunliffe's own detractors but also by media players.
If Cunliffe is announced as the victor he will have to exercise self-discipline and reach across the factions to draw MPs and the party behind him. There is an assumption that Cunliffe will not be able to step up. His grandiosity will annoy many.
It's rather reminiscent of the time when the late Lange was parachuted into Labour's leadership after the hapless Bill Rowling comprehensively failed to best long-time National Prime Minister Sir Robert Muldoon either in Parliament or on the hustings.
Lange's failings were apparent. He was verbally quick but intellectually lazy. But he had the presence and charisma that Rowling lacked. He had the stomach tuck, pulled back on the pies and the booze and bought some new suits.
There was plenty of backbiting within the Labor caucus, particularly over his laziness and lack of intellectual merit. But enough detractors were heartily sick of the long years in Opposition so that they held their noses and ultimately came on board the campaign to dislodge Rowling.
The big difference between Cunliffe and Lange is that the latter was installed as leader by the emerging leaders of Labour's parliamentary A team.
Cunliffe's declared caucus supporters can hardly be put in that category. He has had to rely on the party for votes.
Cunliffe will emerge as victor if the Labour Party itself has decided it wants to win the 2014 election. But he hasn't a hope in Hades of ramming home a victory against Prime Minister John Key unless his caucus colleagues decide they too want to win.