Let's look at the two goals:
To start with, here are our two guiding principles. These ideas guide everything we do.
- Create a version of D&D that embraces the enduring, core elements of the game.
- Create a set of rules that allows a smooth transition from a simple game to a complex one.
Simple to complex? Why would I ever want to buy that? I barely have time to read the simple stuff and he wants to sell me the complex. Maybe he meant detailed instead of complex. You can add more detail to things by using the same simple rules, just look at fractals.
I want to point out a line Mearls writes "Changing the rules of a game in a fundamental way creates rifts within your community." I'm not sure if Mearls says that as a reason not to rewrite it or as a recognition of the fumbles WotC did with prior editions. Nonetheless he recognizes a great deal of fragmentation and questions the returning of long time players, aka the old school. He puts forth the question "Why go back to a familiar game if you find out that it isn't really familiar anymore?"
He answers it with the following paragraph. "So, the first big picture goal is to make a version of D&D that speaks to the recognizable elements of the game. ... , but the design implication is that D&D Next should deliver the primary strengths that each edition brings to the table. If an edition was good at something, D&D Next needs to do a good job of providing it."
That is wrong wrong wrong, and wrong in so many ways. Mike Mearls should focus on the weaknesses of each edition and bring a solution to them in D&D Next. If I'm comfortable with 2nd Edition giving me a new edition which has all the strengths of 2nd is not compelling enough to change. D&D Next needs to provide me the solution to 2nd Edition's weaknesses.
D&D Next needs to provide a solution to the weaknesses of all prior editions, even if that means taking d20 out of its guts. D&D Next needs to provide the D&D adventure spirit with a new set of mechanics. To do otherwise is to compete at price points with the likes of Pathfinder and the indie community.
It needs to provide a new rule set with a low learning curve that uses emergence as a means to create more detail. Mike Mearls and crew seem obsessed with writing more and more rules on how to do things. He mentions "though people were seeking the introductory product, fewer and fewer players were moving deeper into additional material", and "We need to reverse that trend and make a version of D&D that new players can pick up with ease and that existing players can continue to play by utilizing a wealth of world-class adventure content."
What they hint at is selling more fluff and less crunch. I'm in total agreement with that, but D&D's history has been quite the contrary. D&D design philosophy has always been a "reductionist" one. Writing endless rules as if that were the game. A detailed description of things that can happen, how to handle them and how they fit together to build the whole.
They should consider a more "emergent" approach to the solution. One in which a simple set of rules allows for a more detailed game without necessarily calling for a more complex set of rules. He hints it here "To create a continuum of options and complexity, we need to make a game that has a simple, robust core that is easy to expand in a variety of directions.", but drops the ball when he says "We can't change the core game to accommodate those later options, whether they're new classes or detailed rules for climbing." More detailed rules for climbing? Leave that to the GM, concentrate on content, talk about wall types, issues rogues have encountered through history and let the GM have an understanding of this. Do not fill the book with lookup tables which will only slow down the game. I know you love writing it and enjoy selling it to us even more, but it's not practical and that's the reason most experienced players are not buying it.
I would suggest these two goals instead of the ones presented by Mike Mearls:
1) Write a new game focused on fixing the issues within all editions, even if that means throwing the d20 out and starting from scratch.
2) Focus your sales on content not rules. The rules you build in 1 should be simple and generally applicable throughout the game. All else should be content (fluff) that inspires the GM and players and explains how to use the simple rules (from 1) in new creative ways. That means not a single extra table to lookup stuff in.