I'll be honest, I like Howard Jacobson, but this commits the ongoing error of seeing Corbyn as a cause rather than a symptom. He's popped up, structurally in the right place at the right time allowing for a groundswell of anti-neoliberal/austerian thinking to cohere around his campaign. He seems like a nice bloke I'm sure but I would be very surprised if 90 percent of those voting for him have been seduced by his "authenticity", most likely he is a "vanishing mediator" that allows for new ideas to gain weight, enter consciousness as real opposition, and to shift the balance of power. Rather than Corbyn dazzling the simple-minded of numerous generations with his homoeopathic anti-war avuncularity and comforting, simple truths he has instead been instrumentalized by a range of disparate movements and ideas that are coalescing into a new common-sense. For anyone who has been paying attention ( i.e. virtually no mainstream political commentators) this has been going on for at least the last ten years and accelerated post the crisis of 2008. Corbyn's (anti)-charisma helps but fundamentally he is a flaw in the edifice of  business as usual that is there to be exploited, to get ideas that have gone under the radar into the public domain, to encourage anyone unhappy with current forms of social organization that they are not alone, to persuade us that there are other, coherent. well-formulated alternatives. A channel, a portal, of, affectively, roughly the right dimensions to express the ideas that he will be used to promote. No-one thinks if Corbyn loses that this movement will just all go away do they? It will be blocked for a while, but it will find other cracks, gaps, weak-points through which to assail the given and bring itself into being.

Howard likes a bit of Shakespeare doesn’t he?

There is a tide in the affairs of men, Which taken at the flood, leads on to fortune. Omitted, all the voyage of their life is bound in shallows and in miseries. On such a full sea are we now afloat. And we must take the current when it serves, or lose our ventures.