Oh, I hadn't noticed it. I'm reading it right now.
EDIT:
To be honest, I don't think you can truly roleplay a character in ANY computer RPG. You have a set of limitations put forward by the game itself. Some games are much better (Fallout, Arcanum), some are much worse (Fallout 3, Skyrim). When I mean limitations, I say it in both ways: realistically, a character shouldn't be able to do everything in one playthrough. Yet at the same time, the game can't address for every possible idea the player thinks of. I read someone roleplayed an archeologist in Morrowind. Just how do you do that? Enter the tombs, explore but not take anything? Sure, it's "entertaining", but a real archeologist does much more, and Morrowind just doesn't offer you the tools needed to make that experience believable and entertaining. A DM (and I talk out of my ass since I've never played p&p RPGs) could actually give you an incentive because the game takes place in our imaginations and you can do almost everything you want to.
About the topic in that discussion: you can
try to roleplay multiple characters at once (like I mentioned, I don't think it is truly possible to accurately roleplay
even one character in a videogame). Whether you enjoy it or not is another issue, frankly.
EDIT 2:
Post number 11 on that thread by shihonage exemplifies what I mean. Except I don't consider any cRPG to be a true RPG, since for every build you can correctly roleplay in a game (mercenary in Fallout), you have thousands you can't (roleplay a doctor that cures people, a toilet repairman, and so on). You can LARP both of those (use a stimpak on a sick person and watch as he isn't cured at all, use a Doctor's Bag on a cripple and see him limp for eternity), but can't actually roleplay those roles.
I'm not suggesting cRPGs are not fun, but everyone who thinks they are true RPGs are kidding themselves, fuck I kid myself before typing this out and thinking things logically.