I'm still not sold on the need for class groups (just like I'm not sold on the need for creature types). At some point, the distinction becomes academic.
Absolutely!
It's not a bad thing per se to have these groups, let's have them... but the many posts in this thread and the L&L responses about "class X should not really be superclass Y, they should be superclass Y!" already prove that this categorization is only going to cause useless debate.
I mean, we already have endless discussions on what ability e.g. a Ranger "should" have. That's OK, because when you play the game, it actually makes all the difference in the world whether your Ranger PC can do this or cannot do that. Debating class features is natural and I dare say healthy, because class features
are the game you're going to play.
But then, with the exception of the "core 4 classes", do we really need to artificially create a system of
labels that will only make us argue where each non-core-4 class "should" belong? Do we really need then to
force changes to already designed classes in order them to fit into one category?
This is counterproductive because all non-core-4 classes are already hybrids. If they just slap these labels on them, but don't actually change the classes, then I'm all for it. If they start changing the classes to conform to the lables, then it's really going to cause damage because all those classes don't fit naturally under a single label (as proved by the conflicting opinions here) and will be made to fit by emphasizing one side of them at the expense of the other.
This whole thing reminds me of when you have to fill an application and they ask you to write you "Race". Someone has decided that there's a list of N races, and one box must be ticked. What if you're dad was caucasian and mom afro-american? What if you grandparents were japanese+scandinavian+caribbean+arabic? No, you have to tick one box or you can't submit your application. But whose fault is it? Is it yours, your grandparents', or is it the fault of wanting categories at all costs, and wanting to fit everyone under them?
I don't think feats or magic items need to give much reference to the underlying "group."
I am thinking the same.
On one hand I think I understand Mearls' idea: should they design a magic item, it might be easier to say "can be used by all Mages" instead of saying "can be used by Wizards, Sorcerers, Warlocks...". The list of superclasses is very likely going to be fixed, the list of classes might not be fixed, although they said they want it to be.
But on the other hand, how often does it really happen that you need a magic item like that? Traditionally,
scrolls and
wands (and other items that cast spells) can be used by those who have the spell on their class spells list. You can't say "usable by Mages" if different classes under Mage have different spells lists. Almost every other magic item works the same for everyone, or works only for those who have a specific ability, no matter the class. Occasionally there is magic items that work for a specific class, like "a Holy Avenger in the hands of a Paladin...", which you still need.
So that's the whole point: how the hell superclasses are going
in practice to be useful for magic items, when the vast majority of magic items never actually worked based on class groups?
Furthermore, we are going to have lots of subclasses designed as crossovers, such as Fighter subclasses that casts some Wizard spells and Wizard subclasses that fight better, so that you can make your Fighter/Wizard PC in ways other than multiclassing. For these subclasses, will magic items work or not?
Simply, magic items work based on what you can do (i.e. if their benefit applies to your capabilities), not based on what you are, because "what you are" i.e. what's your class name (or superclass name or another label) is nothing in the fantasy world, it's just a label. Unless it represents something real, like alignment, race or (very rarely) class indeed, but creating a system of additional labels when the game is going to be full of exceptions sounds quite unreasonable to me.