This is an edited version of one of my own comments to my post on Rules Lawyering. Commenter Alex suggested I post it in its own right, so here it is. If you enjoy, great. If not, look forward to a real post tomorrow.
In discussing D&D 4th Edition on the official forums and elsewhere, there's a lot of importance placed on the concept of Rules As Written (RAW). It's something that can be difficult to understand for those who've made the transition from previous editions.
Prior to 3.0, large tracts of the D&D rules were skeletal. Not only did the rules envisage you creating your own rules to resolve many conflicts, but the Rules As Written were in many places contradictory and unplayable. As a result, the tradition of homebrew is so deeply embedded in the D&D community that playing 100% by-the-book is psychologically repellent.
It's an attitude we need to change, though. D&D has evolved, and the design philosophy behind it has sharpened. 4th Edition specifically intends to be a comprehensive ruleset, at least in so far as it applies to combat, and for better or for worse it's not content to leave lacunae, loopholes and handwaving
As such, Rules As Written is an essential concept for use in discussion. Everyone homebrews, but there's only limited utility in discussing everyone's homebrew. If you take homebrew as the default state of play, you never end up with better core rules. Your game becomes increasingly self-customised and the value you're getting from your purchased official material becomes progressively less.
To design and develop a better game it's essential that the discussion engages with the rules as written. Having a vague dissatisfaction with a game mechanic and ignoring it in your home game is great for one group but it's much better to precisely identify why the rules as written do or not work to improve the game for everyone.
I, for example, don't use the lighting rules. They're just too much trouble. But I understand how they work, and if a future expansion ever does something that makes them attractive again I'll revisit them.
The RPGA (Wizards' official organised play organisation) confines itself strictly to rules as written. And I think that's good for the game. Knowing that there's a place where the literal interpretation of rules will be viciously exploited in any way possible provides a spur to the developers to make better and more robust rules.
I've spoken before about how the philosophy of game design in videogaming is decades ahead of where RPGs are at, and I think this is one reason why - there's no "homebrew" in that medium. You have to get it right.