I'm glad they are attempting to address the problem of balancing threats for encounters as DH (and the other sgames tbf) are horrible at this.
But does it work?
Looking at the antagonist in the adventure at the back of the book, he has (as a master) a Threat level of 35! This means that you need a party of at least 6 pc's (starting at 1000xp) to take him on - according to the system. This assumes that he's not so powerful he can't one shot either of those pc's in one action (unlike the antagonist in the Black Crusade adventure!).
The Daemonhost statted next to him has a Threat level of 40! I can't imagine many player groups being 6 let alone 8!