Once again we return to the topics of fluff and crunch. These terms appear to originate with Games Workshop, particularly with the 40k line. In their original usage, crunch applies to the numbers section of an army book whereas fluff is the attendant stories of those armies. Why do I hate these terms, then? They seem useful, they describe an element of reality, particularly in Games Workshops products where story and rules are separated by an impassable divide.
The answer is, of course, I don't really begrudge them for the wargaming crowd. They are applicable there, even if I find it a distasteful design method. They mean something useful which can be discussed by using the linguistic tools available, namely that the background of an army is its "fluff" and the manner in which it works is the "crunch." Of course, this suggests that the background is less important, which is true for many wargamers. They don't care who their armies are, just that they are an extension of their will. This is an attitude taken from games like Chess—the White Pieces don't have any personality distinct from the Black Pieces.
But this division is a lethal mind-poison in terms of roleplaying games. First, it suggests that the two are separate and refer to different things. The statistics for a sword are crunch, the description of the sword is fluff. What a bizarre and useless differentiation! What is worse is that routinely making use of these terms destroys the unity of rules and lore (my preferred terms, since they do not denigrate or elevate either element).
The problem has become a deep-seated flaw in the way games are played. Rules should describe, mechanically, the same things that lore describes. When the lore says one thing, the rules should reinforce it with the way in which they are built. This produces a setting that is joined seamlessly with its rule-base, one in which we understand the rules because every rule has a one to one correlation with action in the setting. This prevents the creation of rules that don't make any sense or which seem to contradict established setting canon. Of course, there is a certain upward limit to this kind of seamless joining; go too far and you'll have a Hârnworld which is unplayable by the majority of the population. But, I would argue that going too far is better than not going far enough!
AD&D solves this problem by relying on rulings to join the gap between rules and lore. When the rules no longer represent something that makes sense either in the physical realm of reality (I jumped from a high mountain and fell 10,000 feet: do I live?) the DM is called to make a judgement call, and in most seriously played games that will be on the side of the more realistic option. The DM might even go so far as to do some brief but informative research on realistic ways to interpret events! Can you live with an arrow-wound to the throat? Research will tell you that you may indeed, though it is unlikely. The same goes for a sword-cut to the skull, for there is evidence that many men lived and recovered (perhaps never the same socially) from devastating head-wounds.
But AD&D takes a no-nonsense view with canon deviation. If the rules say that a wizard must study to memorize his spells, then that is what must happen. If the setting requires a different manner for wizards to prepare or maintain their magic, the DM will change the rules. The canonical lore must always be in line with the rules. One is not separate from the other, but rather a representation of it. Whether rule or canon changes, the change is always reflected in its partner. That is because in truth, the two are only separate when you forcibly conceive of them as such. It is their nature to be conjoined, and only through hard work can you separate them.
It is in vogue these days to take the rules for one thing and then call them another thing. The best example I can think of is the Muscle Wizard; while it may be tongue-in-cheek it is highly representative of the kinds of rules/lore breaks that exist both in homebrew 3.5 materials and in the main 4e books. The Muscle Wizard is a simple enough concept: make a wizard character, replace the descriptions of all his spells with various wrestling moves. When he casts burning hands, say he is using his Clothesline; when he casts disintegrate, say he is punching you in the solar plexus, etc.
Most people reared on modern systems will see no problem here. Everyone will laugh and agree that it is silly but that, at its core, it doesn't violate any precepts of roleplaying. Why not "fluff" your character however you want them to be? It's your game, right? Well, sure, in a way. But by doing that you are depriving yourself of a better gaming experience. You are forcing the rule system to conform to a canon that makes no sense and was never intended for it. It isn't creativity, as many people seem to think, it is a profound laziness. If you really wanted to make a suplex-wizard character you could design the class and give it a set of supporting rules that accurately represents whatever Muscle Magic you wanted them to use. Instead, because you are lazy, you have modified an already existing character class in the most humiliating of ways.
While imagination is at the heart of roleplaying, there is something different between the kind of imagination you use when you are play-fencing in your yard and the imagination you use to pretend that the Wizard class is really a Luchador. For one thing, when you fence with sticks you are doing so because it is the best possible alternative to swords. Any child would prefer to have the real object, even if it had to be blunted. But the when you take the same approach to elements of rules, you aren't constrained by practicality or legality: you can make your own classes. You can make the rules match your canon. You choose not to because you are lazy. There is nothing less creative than that.
Don't you want your game to be the best representation of your imaginings that it can be? I certainly do. That is one of the reasons that 4e eludes me; every single character relies on the same mechanic (which is essentially the mechanic restricted in 2e to spellcasters), making every character mechanically the same. The numbers are different, but the mechanic of use and resolution is standard across the board and it doesn't represent anything real in the universe of the characters. Why can I only use a specific sword-stroke once per encounter? No reason exists in the lore, the reasoning is purely a mechanical one.
This is a plea to put an end to mechanical dissonance. Please, don't use the derogatory terms fluff and crunch when you discuss roleplaying games. Without the ever-hated fluff you'd be left roleplaying Chess.