Which Sort of RPG is The Witcher?

Rock, Paper, Shotgun has posted a new editorial discussing what type of role-playing game The Witcher should be considered.
Okay, Dan's got an immediate flaw which we'll gloss over which is irrelevant. There's no link between the phrase (role-playing) and (create a role and act out that character in the game world). Dan believes that the ability to create a character is absolutely fundamental to the genre. So, Final Fantasy and any other JRPG aren't an RPG which he'd recognise. In the comments thread he says that Planescape: Torment (i.e. You are the Nameless One) is the exception to prove the rule, but - like most exceptions which prove the rule - is just a big nasty flaw. If I made half a dozen games like Planescape Torment, would there now be seven exceptions to the rule? At what point is the rule just wrong? (Clue: As soon as there's an exception).

Riffing off him, and other people's positions, the general argument that a role-playing game is based around the idea of meaningful character customisation. Some (i.e. most western ones) front-load some of it - so allowing you to define your character in a way before you start. Almost all will allow you to customise it as you progress - so the character you are at the end of the game will be very different from the one at the start, and almost certainly very different to what you're mate's character would be at the end (even if they started at the same place). Some would argue that this customisation must be irreversible (i.e. you are changed forever) and some would demand it has to be an abstract system rather than anything justified in-game (i.e. Levels and stuff rather than gaining mechanical bonuses). The latter would mean System Shock 2 isn't an RPG, and Bioshock - which both apply to, as you're able to swap in and out your abilities- certainly isn't. Though the latter would also make Guild Wars not an RPG too. Or City of Heroes with its Respecs, because - surely - it doesn't matter how big the periodical gap between completely redefinining your character is if you can redefine your character.

The second part of the RPG - which Dan doesn't touch - is trope of RPGs resting upon some manner of abstracted statistical element. So your characters abilities will increase, they will do more damage, just because they're a better character without any direct input from the player. In other words, while RPGs can have a player's skill effect the result (i.e. they know when to use certain abilities or whatever), they RPGs are indirect tests of skill. Direct tests of skill are the province of arcade games.