Yeah basically see above, and I thoroughly agree with [MENTION=17106]Ahnehnois[/MENTION] ' point that it's crappy players can't do the same things the DM can do with his NPCs. I *hated* the 4E attitude that everyone must be useful in combat. I love playing Call of Cthulhu because there's always room for a professor who can't shoot an elder thing with a shotgun at five yards.
Whoever brought up the 'make these NPCs' challenge should be shot, because it was ultimately edition warring which has led to me constantly having to defend my simulationism, which everyone here associates with 3E. 3E was flawed, but it doesn't make simulationism inherently wrong. 4E gives you buckets of flexibility in NPC creation but doesn't offer the same courtesy to players. I want 5E to follow simulationist principles, but with the flexibility of being a 4E DM - and I believe this is POSSIBLE, especially with flattened math. Whether it happens is another matter.
I don't see this as an inherently worthwhile goal, to be honest. A non-combat character should be focusing on non-combat issues, and combat is the heart of D&D. A non-combat game of D&D is like a game of Vampire: the Masquerade which doesn't have any vampires in it. A game of Shadowrun where everyone sits around and has a tea party. A game of Paranoia where the Computer suggests a nice, sane, sensible mission, gives the PCs tools to complete the mission that are well documented, and everyone cooperates to accomplish the task.
Your character is not defined by his combat ability in D&D, but the mechanics of the character are driven by the fact that this is a combat-centric game. Take the mechanic of levels. What do levels do? They make sure everyone is on the same "level" for combat encounters. Level-free heavy combat games inevitably run into problems where certain people are Physical Gods while others are cardboard tigers (see: Exalted). Or they just make a high lethality game where death is inevitable and expected and character advancement is minimal.
Also there's the fact that there's
two types of simulation! This has not been adequately discussed.
Type 1: Simulationism of rules (aka the top down approach)
The game rules attempt to simulate a reality. Everything is made according to the game rules, top-down. Where the rules conflict with setting structure, rules win. Everything follows the template laid down in the rules, and if the outcome doesn't make sense it is handwaved. Exceptions are rare and apparent.
Type 2: Simulation of outcome (aka the bottom up approach)
The game world is described and created to be consistent. Rules are created to match what characters in the game world are capable of doing. Applying different rules for different situations is fine as long as the rules encapsulate what is occurring and fit the narrative. Where the rules conflict with setting structure, setting wins. Exceptions are commonplace and hard to distinguish from "business as usual."
Simulationist applies solely to people in group 1. Creating a rules structure to define reality.
Group 2? I find that leads to a much more compelling experience, for me personally. I like consistent settings, even if rules are being fudged "behind the scenes."
I hope this adequately explains why so many of us in Group 2 like our approach, and the goals that we are trying to accomplish with our system.