From the discussion on EN World, where I posted this:

D&D has always been about having its major roles filled – particularly those of Fighter, Cleric and Magic-User. (If you check the early modules, there’s a lot of talk about balanced parties there).

D&D 3E not only wants the four roles to be filled, it provided a bunch of other character options that couldn’t provide substitutes… and not only that, weren’t strong enough on their own to contribute meaningfully in combat. The bard is a classic example: most parties are better with a bard, but the actual bard player is spending most of their actions just casting buffing spells and singing, not doing the fun things of, you know, attacking the enemy!

Want a Druid instead of a Cleric? Sorry – you can’t heal as well, and if you need restoration you’re *really* in trouble.

In D&D 4e, what I’m getting is the following vibe from the designers:

* It’s not going to be quite as necessary to have a particular role in your party. No Leader (or healer)? No problem – you’ll be able to proceed on; there will be other mechanisms that will allow you to survive. You’ll still do better with a Leader, but you can survive without one. (reference: http://www.wizards.com/default.asp?x=dnd/drdd/20070831a)

* However, each class will be good at the role it’s made for. Regardless of whether you play a Cleric or a Warlord, you’ll be able to do all the things you really need to do – you’ll be able to heal the party and inspire them. You can fulfill the Leader role. You will have things you can do that the other classes that are Leaders can’t do, so you’re by no means going to be a carbon copy… but choosing the Warlord over the Cleric won’t hurt the party because you’ll be able to do all the important stuff.

 

Like it or not, in D&D, over half the time is likely to be spent in one combat or another. (It’s also the time the system mechanics come into play most strongly, so you’d better make sure they work). Thus, a huge part of doing an effective character design is giving a class a strong role it can fulfill in combat, and doing so the player can choose effective and enjoyable options each round.

That’s the problem with the cleric casting heal. Sure, it’s effective, but it’s not enjoyable for the player, who sees his friends hitting the monsters with swords and blowing them up with fireballs.