I don't share your view of the purpose of classes (I list five reasons to use a class system there, and I wouldn't rank "stops you from doing other things" among those virtues). We can have fighters casting fireballs and rogues casting healing spells, just like we can have wizards using swords and clerics using thieves' tools. While I wouldn't expect these to be the default, I would expect the game to enable me to swap out whatever fighters get at level 5 for the ability to cast
fireball if it made sense for me in my game. If that change is going to suddenly make the character not a warrior or also a mage, because now that character needs to be able to use a wand of fireballs....yeah, that's hugely unnecessary.
I went back and read your article. Weirdly enough, I find that "It's more about what you can't do than what you can do" intersects with your 5 reasons, but especially #2 and #5.
But it's apples and oranges, really.
You're talking about virtues (I'd call it "goals" or "objectives" personally because using such a "charged" word like "virtue" has the nasty side-effect (unintended, IM sure) of putting your opinion up there on a pedestal and opinions that disagree way, way down below. Not good for debate).
I myself talk about how they're built ("classes list things a PC can and can't do"). Notice that there's no commentary implied about whether it's a good or a bad thing.
The thing is, to come back to your article, you mention
Streamlining Decision-Making as one of your 5 virtues. I happen to agree a lot with that. It's just that your "fighter learning fireball" example seems to be in direct contradiction.
But if my ranger is a 1e-style ranger with wizard spells, that's not something the system should be able to handle?
Without any more details about how such a ranger would be defined, I can't really have an opinion on this. It could go either way:
1) If the ranger casts spells in a spontaneous / instinctive manner (
à la Sorcerer), I'd say no, he can use scrolls. But that's just my taste. If the game went and said such a ranger can use scrolls, it wouldn't be the end of the world to me;
2) If the ranger is more of an "academic" wizard, with a spellbook and all, I'd say yes use scrolls. After all, if he's using a scrollbook, he can surely use a scrollpage, right?
So there you have it, and even though it's a bit tangential to the debate: if someone uses a spellbook to learn his spells, he can use scrolls. Clear, logical, coherent. [/sidetrack]
Again, I can think of at least five reasons, and none of them are prohibitive, because forbidding things isn't really the point of a class, as far as I can see. Rogues don't generally know healing magic because rogues generally have no reason to learn healing magic [...]
No reason to learn magic? Why the hell not? Is he never wounded? Does he think he will go through all of his adventuring life without having his life threatened at least once by injury, poison or some such thing?
[...] not because the game would be abandoning all semblance of a class system if they learned it. Maybe the thieves in my campaign are theives of life who steal years from others and give them to their allies, and they belong to a guild that opposes the dominant church of death and light where shimmering knights of undeath defend the realm from outsiders. The game should make it easy to do that [...]
First of all, before I address this, let me stress that I find your example to be an extremely corner case, that has no basis outside of supporting your argument.
That being said, are rogues/thieves really the best way to represent what you're describing? Your "thieves of life" are stealing life, that doesn't make them thieves.