Ok. I can get behind this. I didn't realize it was something that needed to be called out/specifically addressed. But the fact that they want to is, overall (as far as I can see) a good thing.
To summarize most of your concerns, I believe the article isn't trying to "address" anything. It's just an article that is explaining their definition of the D&D "feel" and what that caused them to think about when designing D&D Next.
People were interesting in their decision making process and this article is mostly an explanation: Here's what D&D "feel" means to us. It might mean other things to other people, but be prepared that when D&D Next comes out, it will attempt to get this feel down rather than any other.
If that really, though, a "Narrative mechanics" game thing? I mean, even the best role-player has the player knowledge and the character knowledge...and I'm not sure that one can [really be expected to] decide things without the other. "Is it a good idea to use an encounter power now" seems no different than spell casters having to decide if this is the right round to let loose with the fireball...or to Turn Undead now or let the fighter keep hacking away...or backstabbing now or waiting for a more "dramatic/climactic" round (like, say, when the fighter goes down, the thief dives out from the shadows and delivers the killing blow before the foe can off the bleeding fighter)...or raging or shapeshifting, etc...
This is a debate that's been going on for some time. More than one thread has discussed it here at ENWorld. I agree, I don't see any real difference between "Should I use this Encounter power now or wait until later" and "should I use this spell now or wait until later?" However, the key difference is that an Encounter power for a Fighter might be something that a Fighter could reasonably do every round instead of once per Encounter. So, the limit of once per Encounter isn't something your character would ever consider. The limit is placed on the power for metagame purposes(it would be too powerful to allow it to be used every round).
This causes the decision making process to be different for you and your character. You are thinking "Should I use this Encounter power now? I might need it for later. I only get to use it once." Your character is thinking "Should I try tripping the enemy, going for the throat or kicking him to knock him off balance to set up for a more devastating attack?" Once you've used up an Encounter power, your character doesn't know it's been used up. He chooses not to use it for entirely different reasons than you. Even what those reasons are have been debated ad nauseum. Most people believe they are narrative reasons however...no appropriate opening to activate the power, pain in one of your limbs preventing you from getting it just right, or something like that.
That's why I referred to them as narrative mechanics. They are mechanics that create an interesting narrative at the expense of "realism". They prevent you from spamming the same powerful move over and over again but without any in game rationale for why it isn't possible.
They are merely pointing out this is the baseline. No?
Yes, they are just explaining their definition of D&D "feel" to them. And likely explaining that there may be better spellcasting systems that would be more balanced or more true to the source material, but they've made their decision to make D&D Next FEEL like D&D no matter what the cost.
What does this mean...the same speed?
If your character can decide to do it in 2 seconds, so should you. So, you and your character act at similar "speeds". You don't spend 10 minutes trying to decide which attack to use because each one is complicated enough that you need to read through it again each round to find out if its an appropriate time to use it.
We're all good with this. No?
I doubt everyone is. There will definitely be complaints that the combat system is "dumbed down" because all you do is roll to hit and damage. Where's the realistic trip and grapple rules? How come I don't have enough options in combat?
Some people want very detailed rules because they are more "realistic". I believe they were pointing out that we wouldn't be getting these in D&D Next in order to make sure the game resolves quickly.
Iiiii'm not sure what this argument could mean? What would be something to simulate that might take months in game-time? And, regardless [to a degree], do people not know how to handwave in-game time? If something takes 10 minutes to do at the table...and you say "It's been 2 months in the game world"...who's complaining? And why?
I believe they were just explaining their game design philosophy: Let's make the mechanics more abstract in exchange for quick resolution...but we can allow ourselves to write more complicated mechanics when the in game action you are simulating would take a long time.
The example given was mechanics on running a kingdom. You might have "turns" that last a month. You might design rules on what kind of actions you can take each "turn" that use multiple rolls, look up tables and generally take a long time to finish a "turn". The example they gave was you might sit around and discuss what actions you are planning on taking for minutes or even an hour of real game time and those discussions would mirror the kind of discussions your characters probably have within that month as well.
The flip side being to reiterate that when a mechanic is supposed to simulate something fast like one attack during a couple second long round the game shouldn't require a large amount of thought and discussion and consideration on what to do.
The speed of the mechanics should reflect the speed of the action they represent.
Ooookay. No one's arguing against this, are they? I mean...it really isn't arguable...nor, again, is it the kind of thing I would think Mearls needs to call out/spotlight. Isn't this...obvious?
Fairly obvious. However, there are games where this isn't the case. For instance, in 4e, all of your defenses go up every second level. When you get to level 30, you have +15 to your AC and you are harder to hit while wearing leather armor than a 1st level character is while wearing plate mail.
He was also saying that it can be easy as a designer to think "This monster is level 15, so it needs to hit hard, I'll give it a 18 strength so it does more damage" without thinking about the fact that the creature is an Orc and that the level 5 Ogre only has a 17 strength so now an Orc is stronger than an Ogre.
I believe this was supposed to point out that they were trying to avoid that way of designing the game in exchange for mechanics that more directly reflect the in game description of the mechanics. It seemed as much as a manifesto that likely was originally written for the rest of the designers to constantly remind them to consider these things as anything else.
Would not defining it in [too much] detail mean you DON'T have to worry about these things...the rules will tell you.
But the fact that the rules exist mean you have to spent time to remember those rules and consider them each and every time you use the ability. When you are attacking an enemy, the thought process is no longer "I attack the enemy in his vital spot!", it is "I attack the enemy in its vital spot...wait...is this creature an undead, elemental, ooze, construct or other creature with an immunity to Sneak Attack? Can I reach its vital organs or is it too tall? Is there something else that prevents me from getting to its vital organs?"
Having to go through that thought process can slow the game down. Perhaps only by seconds, but those seconds add up after a while. Especially if every mechanic in the game is designed like this. Each of them adds their own couple of seconds to consider all the exceptions and details.
So, again, I'm really not sure what it is he's trying to get at here. "Designing D&Ds balance to please everyones is hard"? Uhhhh yeah. duh. Shouldn't promised everyone everything they know and love and, maybe, drawing some lines and sticking to your guns would have made things easier. That's why you're the guy makin' the big bucks. Quit'cher bitchin'.
I'm fairy certain this article wasn't about bitching. It was about needing to put out an article that makes it sound like they are open and communicating with the fans. So, in order to make the fans feel like they are part of the game design process they posted an article explaining what they had already decided to do months or more likely years ago.
Likely so that people can read their rationale for everything and say "Wow, I agree with all those design philosophies...I'm going to love D&D Next! It's obvious that they are purposefully designing the game to be less like 4e!"