Given that roles are a 4e invention, pre-4e wizards, fighters, etc. also did not fill the same role.
This is absolutely and completely 100% false. Take a look in a 2e PHB. It has roles. The roles in question are IIRC Fighting Man (Fighter, Ranger, Paladin), Cleric (Cleric, Druid), Mage (Wizard, Illusionist (which had been demoted to a specialist wizard), other specialist), Rogue (Thief, Bard). And mysteriously they fit the archetypal four person party of magic user, cleric, fighter, thief in exactly the same way 4e does.
For a slightly more interesting example, look at 1e. Look at the Monk class in specific. The class itself makes little sense when looked at for the first ten levels (i.e. the overwhelming majority of play) - that 2d4 hit points at first level is just plain weird and their combat was terrible. On the other hand if you treat the monk as an explicit variant of
thief, with thief being the role, the whole thing makes perfect sense. Monks were a type of thief who was better at running away, falling off walls, and playing dead (all useful to a thief).
The pattern on roles has been oD&D barely needed them because there weren't enough classes, 1e had them, 2e made them explicit,
3e dropped them and ended up in the sort of complete mess you'd expect, and 4e brought them back. The 4e roles are, of course, different from the 2e ones - at least in part because with the change from backstab to sneak attack wrought by 3e the role of the thief/rogue had significantly changed.
I don't see this at all. I mean, all editions of D&D are generally considered to be balanced.
This is in no sense true either. It is possible to find people who consider any given edition to be balanced - but if the 1e PHB is balanced then the 2e one isn't (Weapon Specialisation is a
huge boost for fighters) and Gygax has stated on these boards that the classes like Cavalier were added for balance purposes. Also I know very few people who consider 3.X is anywhere approaching balanced.
The mechanics here don't match the goals and are inconsistent with each other. If you want a big hero not to be subject to a fluke of the dice, you should write rules that prevent that explicitly and specifically, "hero points" (or action points or some other such mechanic).
You mean like hit points? Which were written for just this purpose and have just this effect. As Gygax was clear about.
Originally Posted by AD&D 1e DMG, page 61
Damage scored to characters or certain monsters is actually not substantially physical - a mere nick or scratch until the last handful of hit points are considered - it is a matter of wearing away the endurance, the luck, the magical protections.
Conflating this concept with hit points (which are primarily about tangible things like how much blood you have left in your circulatory system) was a bad idea.
And this is not true either. Gygax wrote a
lot about how ridiculous considering hit points to be damage was. Even explicitely pointing out that a mid level fighter was, if you took hit points as damage, tougher than a couple of horses. Stone on the other hand has 15hp per inch (and a hardness of 8). A fighter can take more damage from big blows than a six inch thick block of stone. Hit points as damage and blood you have left make no sense.
Or to quote Gygax himself on the subject of hit points again.
Originally Posted by AD&D DMG, p.82
It is quite unreasonable to assume that as a character gains levels of ability in his or her class that a corresponding gain in actual ability to sustain physical damage takes place. It is preposterous to state such an assumption, for if we are to assume that a man is killed by a sword thrust which does 4 hit points of damage, we must similarly assume that a hero could, on the average, withstand five such thrusts before being slain! Why then the increase in hit points? Because these reflect both the actual physical ability of the character to withstand damage - as indicated by constitution bonuses- and a commensurate increase in such areas as skill in combat and similar life-or-death situations, the "sixth sense" which warns the individual of some otherwise unforeseen events, sheer luck, and the fantastic provisions of magical protections and/or divine protection. Therefore, constitution affects both actual ability to withstand physical punishment hit points (physique) and the immeasurable areas which involve the sixth sense and luck (fitness).
Originally Posted by AD&D DMG, p.82
Consider a character who is a 10th level fighter with an 18 constitution. This character would have an average of 5% hit points per die, plus a constitution bonus of 4 hit points, per level, or 95 hit points! Each hit scored upon the character does only a small amount of actual physical harm - the sword thrust that would have run a 1st level fighter through the heart merely grazes the character due to the fighter's exceptional skill, luck, and sixth sense ability which caused movement to avoid the attack at just the right moment. However, having sustained 40 or 50 hit points of damage, our lordly fighter will be covered with a number of nicks, scratches, cuts and bruises. It will require a long period of rest and recuperation to regain the physical and metaphysical peak of 95 hit points.
And you, like so many others, would be wrong.
Balance is balance. It doesn't matter if it's a video game, or a TTRPG. You can break down any power, any spell, in any game ever to determine it's balanced based on the properties I listed above.
You cannot say "D&D is different!" and call it an argument.
Balance is always balance to a specific purpose. The first question is what purpose it will be used for.