Meaningfully difficult, but not impossible. The rest sounds good to me.
'Meaningfully difficult' by default is 'trivially easy' with enough system mastery. Perhaps, 'virtually impossible,' leading up to 'meaningfully difficult' for the most insanely optimized cast-in-melee build (if it's even possible to anticipate such a thing!).
Goodness, no. Spells written narratively rather than mechanically, and subject to a great deal of interpretation, to dissuade the PCs from thinking that magic is something they can own or control. This is the perfect example of where the arbitrary nature of "DM fiat" actually adds to the tone of the game. Magic should be unpredictable.
Unpredictable magic is overpowered magic. You said spells need not to be overpowered, and that it would be 'easy' to avoid. Reliance on every DM everywhere making the right call every time is not, in my book, 'easy to avoid' - more like impossible.
Narrative description and unpredictability, though, would be great in point (2), when it comes to whether a spell can be cast and what unintended consequences it might have. They're just hopeless when it comes to limiting the actual power of spells. To do that, you have to say exactly what a spell does and how well it does it, otherwise, there's not a limit on it's power, at all.
Though, there could very well be a divide, here, as in number of spells castable, between Vancian and non-Vancian casters. Vancian casters, being 'fire-and-forget' rote casters, might have tightly-defined spells that always do the exact same thing every time, while non-Vancian casters may be able to manipulate their magic to do different things improvisationally, for instance (though even they should still have a firm mechanical foundation for the basic uses of their abilities).
Exactly the point. Magic does not follow the laws of physics, or any other particular laws. Thus, whatever actions are defined as possible by the game reality (including the use of nonmagical class abilities, as well as a variety of other mechanics), magic can do things outside those boundaries.
Half right. Magic can also fail to do things well within those boundaries. For instance, in some fantasy world, magic may be absolutely unable to kill (put you to sleep for a thousand years, but not kill you outright - kudos to anyone who catches this reference, BTW), or it may be powerless against True Love or Cold Iron or upon Hallowed Ground. Magic has no basis in fact, so it's power - and lack there of - can be defined arbitrarily.
Early, you argued that it would be easy to create spells that were not 'too powerful,' now you're arguing that for magic to be magic, it's power must be utterly unrestrained.
Now, if what you meant to say was that the things magic does, in nature or in essence, can & should be outside what can be done by mundane means, but need not be of any greater (nor even equal) power, then I'm with you. For instance, making a newly-laid chicken egg hatch into a full-grown songbird is impossible by mundane means (though you might fake it with some prestidigitation), but, while it implies supernatural powers, that trick, alone, is not powerful. And, magic not being consistent or predictable nor following any laws, that ability in no way implies the ability to conjure thousands of brown recluse spiders into you enemy's clothes.
Thus, the basic form of "if a magic class ability (spell) can do/say/be X, I should be able to do something equivalent to X with a nonmagical class ability", i.e.
Quote: Manbearcat ==============
If this is to stay in the game, then other classes beside the Wizard really need abilities "written narratively rather than mechanically, and subject to a great deal of interpretation"
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doesn't make sense.
From a game design perspective, in terms of power/balance, it doesn't. But the reverse does: magic needs to be constrained to be balanced with non-magic-using classes. That could mean no more versatility and potence than non-magic, or it could mean more versatility (able to do things outside the laws that apply to non-magical means), but /less/ potence.
But, I don't think that's what he's talking about. He's talking about a stylistic element. Really, there's no need for the game mechanics to dictate narrative or 'directors stance' as he put it, or not. If a player wants to willfully suspend his disbelief and 'immerse' as his character, he can; if he wants to puppet-master his character from an observer's perspective, he can. Balanced mechanics won't actively 'force' either, they'll just sit there, being mechanically balanced, to be used under either style at the whim of the player.
