Thats fine because this is a completely different point.
If you want to call it a good teaching aid for new DMs I'll offer no arguement.
But I'm not speaking as or for new DMs. Teaching is well and good, but let's also take full advantage of no longer needing to be taught.
I'm not sure what you are suggesting here... that the DMG shouldn't waste space with stuff that is useless to people who are experienced enough that they don't need the DMG?
And as a tangent, the claim of "a subsystem for every single possible action a player might perform" is a total red herring.
Not really, because otherwise it's all a matter of what actions *you* think should have been explicitly defined, which is completely different than what other players think should be defined. What comes up and is useful varies greatly from group to group, and it's impossible to accommodate for everything people want to do, and so they offer some very good guiding principals.
Aside from liking pg 42 for new DMs, do you really disagree with the rest of my statement?
Do think that one size fits all is a good policy?
No, which is why I've stated many times in this thread that just because some people really dislike some design choices doesn't mean that there aren't legitimate reasons for them and that others don't believe they are an improvement.
It's also a good reason to help teach DM's some guiding principals to start with, so that they can then decide what works best for them and their group and adapt it as needed. The DMG does not discourage DM's from making the game their own, quite the opposite.
Do you think GM calls is not a critical cornerstone?
Absolutely, but uninformed and poor GM calls can really ruin the fun too. Again, the DMG offers a lot of suggestions, advice, and guidelines. I wouldn't consider P. 42 (or most other parts of the DMG) to be hard rules, but rather helping DM's get a feel for the art of DM'ing and learning to make their own calls by giving examples of generally balanced resolutions.
Do you think that the merits of a set of mechanics should be based more on one DMs ad hoc rulings moreso than the entirety of the system itself?
Now this is a question that is completely subjective, because it hinges on personal preference.
I personally think that having a bunch of confusing subsystems that have I (personally) would frequently have to reference and re-reference when they occur to not really be a huge advantage to a game system where I am not really trying to run a simulationist style game, but rather just want to focus on story, drama, characters, fun and action.
I think that teaching guiding principals of how to resolve the vast majority of things is a better approach than how to resolve a small number of things hand picked by the designers, which may or may not apply to your particular game.
Over time, these resolutions will likely tend to become increasingly more consistent and solid as a GM learns from experience and learns to apply resolutions from the past to new unexpected actions in the future.
Giving me a better grasp of principals makes me feel a lot more free to improvise and feel confident about it.
In my opinion, P. 42 fits right in with the old adage, "Give a man to fish, feed him for a Day; teach a man to fish, feed him for a lifetime."
However, I realize that some people want everything to be defined in explicit detail. It's a matter of taste and what people feel comfortable with.