Owen Jones’ recent blog contained the best advice to Jeremy Corbyn as Labour leader so far. If he follows it he is certain to fail.

Owen accepts that a Party that aspires to government must appeal to a wide range of views.

That Owen finds this undesirable but necessary is revealing. At times he seems to agree with the strand of opinion that sees seeking common ground as dirty compromise.

I don’t. The achievable, deliverable, reasonable are certainly poison to an unrelentingly radical alternative. They puncture the reverie, and undermine the energy and vigour that it relies on.

Some therefore believe a thoroughgoing radical approach means making impossible demands to shift the debate in a more radical direction.

This is an immoral and manipulative approach to politics. As Owen himself says:

“politicians promising things they can never deliver undermines people’s faith in both politicians as a whole and democracy, too”

Quite.

But if Corbyn is distinguished from the other candidates it is for his refusal to compromise on “principle”.

I dwell on this because the dilemma that Owen never solves is whether Corbyn should reach out to the voters and offer what is achievable or should he make the unequivocal case for these “principles”.

The advice advanced at times is to compromise on rhetoric but stand firm on policy. Elsewhere electoral considerations seem to drive major policy concessions.

Rail nationalisation is sold as a fairer deal for the stock-broker belt. Increasing the state pension above the hugely expensive triple-lock will win over pensioners.

Concerns about patriotism are to dealt with by an appeal to England’s radical traditions. The debate on social security is reframed with reference to house-building, an even higher minimum wage, and focusing on the right “stories” – about low paid or insecure work.

This mixed bag strategy contains much which is a no-brainer - and hence was tried in the last Parliament. We lost so on their own these cannot be the answer.

Some of the ideas are irrelevant. Appealing to England’s radical tradition is straight out of a Blue Labour academic seminar and like Blue Labour that is where it will stay.

But some proposals are straight out of the impossibilist left playbook – Owen mentions Jeremy’s commitment to an increased state pension briefly. You cannot make what Jolyon Maugham has calculated is a £22bn billion pensions spending commitment in passing.

What conclusion to draw? Can we ignore this lack of coherence and conclude that the person of Corbyn, the nature of his support, will itself provide that comprehensive break with the past.

Or should we conclude that despite the media hysteria he can be a mainstream Labour politician and will be much like what came before.

This lack of clarity is the heart of why this approach would be the end of Corbyn’s hopes. Where has ‘authenticity’ gone?

Can a straight talking Corbyn really win by showing concern for the stockbroker or arguing he has a fairer plan to get the benefit bill down? Can he appeal to pensioners on the grounds of security whilst countenancing nationalisation by confiscation – threatening their pensions?

Can he claim honesty but also respond to questions about his views on defence by changing the subject?

If Corbyn ever had a chance to get elected it is precisely because of a refusal to play that game. Owen cannot wholeheartedly argue that Jeremy should compromise because what is the point of Corbyn if he does.

“Trust” is the biggest driver of UKIP support and Corbyn’s biggest asset. He sure as hell won’t win an election as the guy everyone knows wants to spend more on benefits but who is avoiding the question.

As Owen points out three decades of Corbyn’s statements and engagements will be scoured for him saying the wrong thing.

This is hardly unfair. His selling point is that for decades he has stuck by his principles and said what he thought, he can’t have it both ways.

His views on NATO can’t just be quietly dropped as Owen claims. A focus on green tech jobs is inconsistent with his view on coal mines.

He gets credit for standing outside the consensus on Iraq - so he gets the consequences of the same on Kosovo and the Brighton bombing.

This media barrage he will face is not unique. Tory leaders get it too, albeit less so: Cameron’s Bullingdon connections, William Hague’s baseball cap, Howard’s “something of the night about him”.

As Owen says:

“See those guns in the distance? Yeah, well we’re running towards them.”

Corbyn could pursue the SNP, Ukip approach of easy answers - it even has a chance of working for a time.

But what he cannot do is execute Owen’s strategy and continue surfing this wave of yearning for authenticity and anger at managed politics.

Because implicit in Owen’s piece – although he is too grudging to admit it – is an admission that there are no easy choices for Labour leaders and that this approach cannot work long term.

This admission that the compromises of the New Labour years are not a gross betrayal but the inevitable result of politics and policy operating in the real world is welcome.

But once you recognise that you cannot in all conscience support Corbyn as leader. He can’t be straight talking and run away from 32 years of political statements. He can’t represent a new more honest politics and pretend he is nationalising the railways out of concern for the commuters of Tunbridge Wells.

In an age when authenticity and trust is such a prized asset, Jeremy Corbyn has only one card to play.

That his most vocal public supporter and the most intelligent commentator of the hard left begs him not to play that card speaks volumes about how realistic that approach really is.