well, that definition includes Wizardry then! that's all I wanted to settle. Be sure to let Sawyer know he contradicted himself.
The pre-Bradley Wizardries do not allow you to to define and express your character's personality in a way that meaningfully changes the development of the story.
This seems like an arbitrary way to define roleplaying though. Why is roleplaying only valid in the context of a story? Why not in the context of a combat operation? In the latter, different units or unit types can play different roles. Scouts, snipers, assault troops, they all have their roles in the operation. In old-school CRPGs you also have different character types that have their roles both in the context of dungeon exploration and in combat. Mages, clerics, thieves, and fighters - and mixtures thereof - all play different roles. Again, if you don't read anything into the term "roleplaying", this is valid as well. The main feature that distinguished RPGs from wargames, historically, has been character customization (exploration too, but that is less important). RPGs, both PnP and computer alike, always have had elaborate character systems that allow the player to build their character or party in different ways.
The "role" has never in practice been a composite of in-game actions (let alone dialogue choices), but an abstraction (usually quantitative) fashioned from the possibilities offered by the ruleset and the character system, and RPGs have always been notorious for offering a large variety of such possibilities or options, at least compared to other genres. Of course, these possibilities have often also allowed different playstyles, but the mechanics of those playstyles are not exclusive of RPGs. For example, many RPGs allow for stealth mechanics which you can access - or at least only use optimally - only when you build your character as a thief, but the stealth gameplay as such is something you could find in stealth games proper, and in more sophisticated form. This is the case regardless of whether the stealth "minigame" is a full implementation of real-time virtual sneaking, or a heavily abstracted pnp simulation.
What I am trying to say is, RPG gameplay can be anything, it can be CYOA, wargame-style turn-based tactics, dungeon crawling, or stealth. That is not what matters, what matters is that the gameplay interactions are driven by a sufficiently elaborate character system. This means that, for example, Age of Decadence does count as an RPG, since the dialogue options and quest resolutions that are available to you are heavily dependent on your character build. On the other hand, interactive movies/novels such as Telltale games do not count as RPGs since dialogue options and resolutions do not depend on character build. In that sense, RPGs are a very unique genre since they are not defined by their gameplay components, or at least that is the case in so far as one does not consider character/party building a gameplay element, though it might well be taken as such, as it constitutes an implicit strategic layer that, even in games in which one does not have to micromanage this aspect too much, tends to be the most decisive factor in conflict resolution and the tactics available to the player at any given time.
This argument is further reinforced when one considers the definition of RPGs from a historical point of view, e.g. one defines RPGs synthetically, since in practice this is how most RPGs ever made have been; and as I pointed out initially, even analytically, there is nothing in the definition of roleplaying that discredits these traditions.
