we weren't supposed to see dooku as a consumate "sith" either.
he was supposed to be a distinguished Jedi who left the order because of differences with the council
and was trying to unravel the mysteries of the sith on his own.
he was (supposed to be) playing both sides of the fence.
as the audience, we're supposed to believe that he wants to destroy the sith.
in AOTC he tells Obiwan "join me and together we will destroy the sith!" and he sounds pretty serious about it.
---> if this were coming from Qui-gon I'd have believed it.
and we'd never really know what side the seperatist leader was on. even after Anakin killed him in ROTS.
(ie: did Palpatine let anakin kill dooku because he knew Dooku wanted to destroy the sith?)*
*this question doesn't even come up, because christopher Lee played him like count-freakin'-Dracula.
there's no question he's EVIL. ::) he's christopher Lee FFS (LOL).
if the seperatist leader were played by Liam Neeson (as Qui-Gon) instead, then we would see him as sort of a tragic hero.
ie: he went to the dark side, to take it down from within. and he failed.
proving, ultimately, that it can't be done, and creating tension for the hero....
(like Red Leader in ANH proves the computer can't hit the exhaust port: he goes before our hero, and establishes the parameters of the struggle)
...which would define anakin's story: so the audience knows what he's up against.
also it would give a reason for the Jedi Immortality.. thing.
ie: BECAUSE he would have to be "neutral" (as far as the light-side/dark-side struggle), in order to play both sides of the fence,
this could be explained as a reason why he found the secret to "BALANCE" and ended up as a force-ghost. *shrug*
this isn't explained at all, the way it stands now.