JOHN McDONNELL’S decision to change his voting recommendation on George Osborne’s fiscal charter has wound up Westminster commentators and some attention-seeking Labour MPs.

The usual suspects have queued up to be interviewed by the media and rehash arguments offered to and dismissed by Labour members during the leadership contest.

Serial abstainer Chris Leslie lamented that McDonnell’s U-turn on parliamentary tactics sends the wrong economic message to the public.

John Mann boasted that the rethink was dictated by the decision by him and other backbenchers to vote against Osborne’s charter irrespective of instructions from the shadow chancellor.

If he believes he was central to McDonnell’s change of heart, that’s fine and Mann must be overjoyed by the latest decision.

Well, no he isn’t. He says that it has left the shadow chancellor looking “a bit of a fool,” believing perhaps that this comment will help his party develop its opposition to the government’s austerity agenda.

For good measure, Mann felt it necessary to display his own tenuous grasp on economics by claiming that the leadership’s people’s quantitative easing (QE) proposal is a creation of Milton Friedman and a policy favoured by George Osborne.

There is a huge difference between Osborne’s QE policy of handing cash to the banks to be recycled into corporate profits and the Corbyn-McDonnell proposal to print money to invest in infrastructure, skills, housing and other areas to stimulate economic growth.

The former restricts benefits to the 1 per cent while the latter meets real human need and boosts employment, pushing up tax revenues and thereby reducing the deficit.

Shadow energy minister Clive Lewis is surely correct to suggest that Labour backbenchers whinging loudly for the benefit of the anti-Labour media are merely showing that “they are unhappy with the leadership.”

Democracy can often be inconvenient. Our candidates don’t always win and this may leave us feeling frustrated and upset.

But Labour MPs who didn’t back Corbyn — the vast majority of them — have to bear two important points in mind.

One is the scale of Corbyn’s victory, trouncing his three shadow cabinet opponents in the first round. The other is that he won on the basis of opposing the austerity-lite policies adopted by the Labour leadership and all his challengers.

Corbyn and McDonnell may be a minority in the parliamentary Labour Party, but they are supported by the mass of Labour members outside Parliament.

If anyone is out of step with the party membership, it is the few dozen parliamentary navel-gazers who look for excuses to kick off, who text journalistic contacts with gossip during PLP meetings and who supply back-stabbing comments to the media to undermine the new leadership.

McDonnell will doubtless have learned a political lesson over this episode, having originally signalled his intention to “have a bit of fun” with Osborne’s ridiculous Charter of Budget Responsibility.

He changed his mind over parliamentary tactics, having met some of the thousands of people affected by the government’s abandonment of the Redcar steelworks.

His colleagues ought to show that they too appreciate the hardship caused by the government’s obsession with cutting public services and working people’s living standards and understand the necessity to project a qualitatively different economic and political direction.

They might bear in mind Corbyn’s plan for a gentler and more polite approach to debate in Parliament.

And they might reflect on who benefits most from their uncomradely behaviour at the PLP where they shouted down Richard Burgon in an outburst of unparalleled hooliganism.