I think you really SHOULD read DMG2.
Maybe one day. I have a policy of not spending money on books for games I'm not going to run...
Really, the PLAYERS should know the rules. A 1e style DMG honestly never made sense "Oh, the DM has all the tables and charts, you shouldn't know what your character actually needs to hit anything!" lul wut?
Ah, the 1st Edition DMG. I have actually been reading the 1st Edition books for the first time this year, and finished the DMG last weekend. And I was shocked at how poor it actually is - badly organised, full of tedious minutae in many places, quite confusing at times (I read the initiative rules three times, and still don't understand them), and so on... (Which is probably heretical, I know...

)
However, where the 1st Ed DMG excels is in the appendices, with all that material on building dungeons, stocking dungeons... and the little flavour bits, such as the dungeon trappings, the medicinal uses for herbs, the inspirational reading...
The 2nd Edition DMG is a sad joke. Fortunately, they went some way towards fixing that with the "Campaign Sourcebook and Catacomb Guide". Even so, I don't think they ever actually explained how to build an adventure.
The 3e DMG contains much of the solid stuff from the 1st Ed DMG, and is considerably better organised. Sadly, it spends so much time on dungeon trappings and the like that it's
really dull. Plus, it doesn't actually say much about
running the game - that wouldn't come until the DMG2.
So, yeah, the 4e DMG1 doesn't actually fare too badly in the comparison.
So, yes, DMG1 is all talk. What else would it be? The writing is excellent and it covers a lot of value and I think it actually is quite an excellent Dungeon Master's GUIDE. In other words it is a textbook on the nuts-and-bolts of DMing 4e and a pretty good one.
It's missing two key things:
1) An in-depth, step-by-step tutorial for building the first adventure.
2) An in-depth, step-by-step tutorial for running the first adventure.
The material is there, but it's spread out, and buried in a 224-page book. If you give that to a kid looking to start running games, he'll respond "TL;DR", and just wing it. And then, when it all goes horribly wrong, he'll give up and play WoW instead.
For someone with an advanced understanding of how to DM it may not be all that revelatory and then you're quite right, you could have a 50 page book with nothing but the crunch and a few paragraphs of advice on how it is intended to be used and be done with it.
I would advocate splitting the DMG into two sections. The main section should provide the two tutorials right at the start (with Kobold Hall or equivalent used as the example for the first tutorial, then presented in full immediately thereafter), then continuing with an ongoing tutorial for the DM on continuing the adventures, building a short campaign, then a longer campaign, the basics of a setting, and so on.
The second section, the appendices, should provide all the crunch. Put it all together at the back of the book, so the experienced DM can ignore the tutorials and still find what he needs easily. That's
if we need to have the crunch at all.
So, I think with DMG1 it is a matter of you're probably not the primary audience.
No doubt. I come from a family of educators (while being the rebel of the family; I went into software engineering), so I have fairly strong opinions on how training materials should be presented. And, IMO, the DMG1 very definitely
should be training materials.
DMG2 OTOH has a lot of pretty specific "here's how you can fix this problem" or "here's how you can approach doing this kind of thing".
That does sound really quite good. Maybe I will pick up a copy...