I would hope he is right as well.
Let's assume Boris wins the leadership of the Tories. I would say he has to deliver on most of these expectations or he will be toast when he comes to a general election.
If I were in Theresa May's shoes, I'd support him, give him enough rope to hang himself. If he delivers, no one will complain.
He did a good enough job in London for regular Labour supporter to re-elect him so he can't be that bad.