As long as i get to be the frog
Is it perfect? No but it's a damn sight better than anything WotC or for that matter, White Wolf or Paizo have ever published regarding game mastering. And look - it's only 32 pages! You could easily contain all of that within the DMG. And I know some people love to say "prescriptive", which, frankly is being used as a meaningless buzzword, and quite politically rather than helpfully, but by no means is his book "prescriptive" (unless the 5E DMG is drastically more "prescriptive"). It's just a great example of what an actually-good book on DMing can look like, and how extremely small it can be!
I'd be interested in reading a few exerpts of info not presented in the 5e DMG that is presented in that book so I can make a better judgement for myself.
I'm not advocating for shrinking the DMG, note, I'm just saying, containing everything you need to get a good start on DMing can probably be done by a skilled writer on the subject in 32 pages. And given it's from 2003, I'm sure it could be improved upon.
I'm curious what kinds of topics those 32 pages would cover that the current 5e DMG doesn't. Can you elaborate any?