Hi dig,
I read it and I preferred the Dabiq idea which he rejects. But I granted him the role (from my perspective) of being the source of the idea.
Focussing on Dabiq obliges ISIS believers to participate, so it concentrates them in a single place and, in defeat, it destroys their theology in one go. I have no doubt they will lose a set piece battle in which they have no air power.
So they lose the battle their theology says they will win and removes their prestige both temporally and spiritually. Plus, their most enthusiastic adherents will be in the mosque. The morgue, I mean.
It has the elegance of using their own superstition against them.
For me, that is likely to be the end of the matter. Back to dealing with Al Qaeda, which we have been better at.
I've watched containment long enough to think it doesn't really work. Non-combatants die instead of ISIS people.