Story speed vs. speed of advancement

On holiday without a PC, I'm playing Disgaea on the PSP instead. Disgaea has a story that you access by doing a linear series of battles. But there is a twist: Your characters advance in power slower than the difficulty level of the set story battles goes up. In consequence you are forced to side-track, and either repeat old battle maps or play on the random battle maps of the "item world", which has the added advantage to "level up" your gear. That can be fun if you are mostly interested in character advancement, but might feel a bit grindy if you are mostly interested in following the story. In any case the game got me to think how other role-playing games manage the story speed versus the speed of advancement.

In early World of Warcraft there were some quest series which had the same issue as Disgaea: If you picked up the level-appropriate starting quest, the later quests of the series would be too hard for you once you got there, forcing you to do other stuff to level up before. By the time you could finish the quest series you had half forgotten what the story was about, not ideal. But nowadays in general World of Warcraft rather has the inverse problem: You level up so fast that you can't do all the content of a given level before it turns grey. Fortunately that is just a minor problem, few people are as completionist as to be bothered by that, and you can always play through the left out quests with an alt. Overall there aren't that many clashes in WoW between story speed and speed of advancement, because the story in WoW is such a weak element of the game. Actually the biggest problem you might run into is that if you don't have people to raid with, you advance to such a high level of power with epic gear in the endgame that there is only trivialy easy solo and small group content left.

Next year's Star Wars: The Old Republic promises to be more story-heavy, so I'm wondering how the speed of the story will work out there compared to the speed of your characters advancement. Will there actually be longer story lines in the game? And if yes, how does the game lead people through those story lines and makes sure the content is always level-appropriate?

I think that the defining feature of role-playing games, having character advancement, makes story-telling in these games more difficult. At the final showdown with the big boss battle you want the boss to be neither a push-over, nor unbeatable. Doing side-quests to become stronger is nearly always a possibility, but it breaks up the flow of the main story. Other games, lets say point-and-click adventures, don't have that problem, because they don't have character advancement, and can concentrate fully on the main story. On the other hand there is some indication that players don't all care about the main story anyway. Maybe role-playing games should change the way they tell stories and make the player character more central to how the story is told and chronicled. Players are likely to be more interested in their own advancement story than in saving yet another princess.