Most try not to raise raise false hopes. You have a strategy which no one understands but raises false hopes.
Let me try being clearer and perfectly honest
1) I think we need vehicle capable of giving electoral expression to anti austerity politics
2) At the same time, the overriding imperative at the next General Election will be to kick out the Tories and LDs - Labour will be the chief beneficiary
3) As yet Labour's policy stance is unformed, what little there is seems contradictory or inadequate, but is being contested from inside and outside the party and the wider labour movement.
4) The task is therefore to maximise pressure inside and outside on the Labour leadership and build confidence in and around the idea of resistance to austerity
5) The process of doing that ought to see what remains of the Labour left look outward and work around common aims with forces outside the party (building an anti-austerity bloc), whilst also maintaining pressure on, and exposing the inadequacy of, official Labour policy.
6) Pressuring the leaderships of the affiliated unions to demand influence in return for funding
What happens if, as is quite possible, the above fails to have achieved sufficient results? Well, then that will be the stage to reassess whether Labour has become so toxic that *tens, hundreds of thousands* are willing not only to break from Labour but can be won to a socialist alternative. Trying to pre-empt this only undermines credibility that such an alternative is possible. But having utilised the mainstream platforms opened up to Labour party members, and consolidated links with forces outside, such a left would be in a better position from which to think about how a new party could be built.
I don't claim this is any earth-shattering innovation or insight. It is by and large what is already happening. The Labour left isn't the alpha and omega of what's needed, obviously. But dismissing its strategic relevance altogether is to be blind to the roots of Labourism in popular consciousness. The fact that someone like Ken Loach - in the Spirit of '45 - is effectively looking to rehabilitate a version of classic old Labourism shows that.