Cabinet or caucus reshuffles are the stuff of nightmares for Labour chiefs.
The need to accommodate gender, ethnic and other factional interests must be balanced against the need to go into parliamentary battle with the the strongest line-up possible.
David Shearer has pulled it off. Yesterday's reshuffle of shadow portfolios is very different from the one he instituted on becoming leader 14 months ago. His reluctance then to tread on too many toes after beating David Cunliffe in a post-election ballot left Labour fighting National with one hand tied behind its back.
The net effect was that of the five priority areas identified by the leader as critical to the party's 2014 election chances - economic growth (or the lack of it), housing, jobs, health and education - Labour has been all but invisible in the past three.
Those portfolios were held by MPs not well disposed to the combative side of parliamentary politics. At the same time, some of Labour's heavy-hitters were left with minor portfolios. That imbalance has been remedied.
Deputy leader Grant Robertson, who had held the environment portfolio, is now in charge of employment and training, thus harnessing one of Labour's best and brightest to what is shaping as the No 1 election issue - jobs.
The switch also ups the ante on National by making a potential future Labour leader face off with a potential future National leader, Steven Joyce. He has largely had an easy ride until now. Robertson nobbling Joyce would be a major scalp for Labour. But vice versa for National.
Likewise Annette King and Tony Ryall in health. King had barely had the role for five minutes when she lashed into Ryall.
It is not so much the case with Chris Hipkins in education. Hekia Parata is already beyond redemption in most people's minds.
Shearer's clever reshuffle also makes use of two other long-serving, but highly effective MPs. Phil Goff has been given licence to make trouble for National across the whole public service - rather than just the Ministry of Foreign Affairs. Similarly, Trevor Mallard has been given the shadow internal affairs spokesmanship which covers issues such as ministerial travel and credit card spending.
Where Shearer has demoted MPs - except for Lianne Dalziel, who falls out of the top 20 - he has shunted them down only a few rankings.
He has also made it pretty clear to Cunliffe that there is a road back from the wilderness.