Balesir
Adventurer
I'm going to disagree with some other posters, here, in that I think the intended and primary use of monster roles in 4e is descriptive, not prescriptive. It's basically a shorthand that tells the DM what role the creature is generally most suited to play in combat (it only really applies to combat, although if the monsters have a door to bust down they'll likely look to the Brutes first to take care of it).
The matter can seem confused because of the table of HPs, AC, attack bonus and so on by role and by level in the DMG - to some this suggests that a monster of a given role and level must follow a prescribed formula. The text of the DMG, though, makes it pretty clear that some variation around these "norms" is not just allowed but expected and positively encouraged; for further evidence of this you have only to analyse published monsters against those tabulated values to see that they are frequently quite different.
The thing is, though, that carelessly applied variation can remove the descriptive value of the role and level labels. This, too, is cautioned about in the DMG. Following the monster design "guidelines", there is no reason you couldn't make a Brute with an unusually high AC, lower than usual damage and powers that tended to immobilise, slow or debuff foes attacking allies. The problem would be that what you have designed is, functionally, a Soldier rather than a Brute. Since the role is only there for your own help and guidance, and you have just given yourself a bum steer, there is really no good reason that you would do so, though.
Likewise with level. Could you design a monster that is better in all categories than the average monster of your selected role and level? Sure - but, in reality, you have just designed a higher level monster. If a DM wants to deceive him or herself and deliberately short the players, they can do that - but why would they?
First off, the article is talking about monster roles, rather than class roles - and the functions of these two things (in 4E) are very different.
Secondly, the roles for character classes are very useful for giving players a "bluffers' guide" style idea of what a class can be useful for, in combat. Given that it has value in this sense - it tells us something about what the designer had in mind when building the class mechanics - I would much rather see it included than not. Hiding stuff because it's "dangerous knowledge" that "you don't need to know" pretty much always strikes me as a dumb and frequently suspicious thing to do.
