What about a situation like Fallout where you are under time pressure to complete the main story or Baldur's Gate where if you wait too long, certain characters will not be able to join your party. A walkthrough could be really helpful in cases like that, especially if the game didn't alert you to the fact that if you progress beyond a certain point, you won't be able to achieve "X".

Nope, serious. From memory for Oblivion its: Goto monastery, ride to hidden fortress, kill some chap, big dude rises, end of quest. Same for skyrim, but replace chaps with dragons, oh and starting isn't on a prison ship for a change. Don't get me wrong I really like the games, just the main quests leave a lot to be desired.

The Elder Scrolls games are an interesting beast. The main quest doesn't take that long (especially if you can use glitches to skip most of it), but there are a ridiculous number of sidequests and optional areas to explore.
I would argue that it is a failure on the part of the game designer, especially if the game doesn't alert you. Remember, even Wizardry 4 alerts you that you might get stuck after a certain point if you lack a certain item.

You didn't play Baldur's Gate I, did you?:) If you don't follow quests of your party members, and will go do some other stuff even for a bit, you will be out of time. There is no explicit timer either. Walkthrough is also needed because you want to get all your party members asap before they are level-scaled with DISASTROUS Max HP rolls and bad/missing proficiencies.

^ This.

I tried playing Baldur's Gate without a walkthrough, but then I took an arrow in the knee.

Funny thing: I got divine divinity and played it through with a walkthrough as well. Only, due to the various glitches on the gog.com release version, I stopped playing and only got back to it years later, continuing exactly where I had left before.

It probably was the walkthrough helping me find and do almost every side quest, but I don't have the slightest memory of any trouble in beating the last boss.

I tried, but I quit after my level 1 party (which had been level 1 for way too long) encountered an enemy that cast Improved Invisibility, which is not something a level 1 party could counter. Also, low level AD&D is not fun. (I explained the problems in another post somewhere.)

I think being a "completionist" is not conducive to roleplaying and ditto with using walkthroughs. I think that the idea of roleplaying is to take on a specific role and then stick with it. That means only doing what your character would do and not what you, the player thinks is the best course of action via min-maxing.

A walkthrough and especially a video-guide can be great if you are stuck but using it all the time sounds like a way of gaming that is the antithesis to play and games. In other words RPGs are about creativity and taking on a role and you don't do that as a completionist or using guides 100% of the time.

But obviously you can play your games the way you want.

i used to have to pay good money for printed official strategy guides. Online walkthroughs are so much easier on my wallet.

I consult a walkthrough in 3 cases.

1. Before beginning a game like Baldur's Gate, Neverwinter Nights or Fallout, to check character creation and tips so i wont have to restart a game.

2. When I am stuck at a certain point, a puzzle or quest.

3. After finishing a huge area to see if there are any quests that i have not done.

I use Gamebanshee for 2 and 3. Always satisfied.

That's my main reason for using a walkthrough as well. I don't want to miss out on any fun content or experience just because I missed a certain NPC or item. Trails in the Sky is a particularly devious example because you need all of the bracer points to get the maximum rank, and it's easy to miss them because the game world is so huge. Especially the Carnelia books, which get you a very nice reward at the end of the game. There's usually a window to talk to a certain hitherto unimportant random NPC on the street in a completely different city while the plot is urging you to catch the bad guy or something. That NPC is practically impossible to find without a walkthrough, except if you want to talk to literally every NPC (there must be thousands of them) in the game world after every plot point.

When it comes to games like Dark Souls and Dragon's Dogma I normally use walkthroughs, otherwise those games get far too tedious when looking for all the crucial stuff and I stop enjoying the game. The open-worldness in those games simply don't pay off to me. Following a walkthrough makes them more linear and thus more enjoyable. In most RPGs though, like the Risen series, I only use walkthroughs if I get stuck in some way.

Here's a nice fellow explaining exactly what I meant when talking about stopping playing Trails in the Sky.

I'm a completionist but I don't like using walkthroughs. I prefer it if exploration and saving/trying different options/reloading is enough to get the most out of the game. Sometimes, if I'm unsure what to do or what consequences something will have, I sneak a peek in a walktrough, but then I wish I didn't have to, and I never start playing an RPG with the walkthrough already at hand. Don't like reading guides either.