The problem is tied to the setting and to player motivation. If the motivation for an epic campaign is directly tied to the PCs, such as a the last survivors of a battle seeking vengeance against the foreign king, then new PCs just don't have the same focus, even if they have the same objective. If everyone is dead, then that original connection is completely lost. In non-epic campaigns, it's pretty easy to make adjustments, but in an epic campaign the flavor is completely lost. I've had it happen a couple of times, and while I tried to continue the game, the players told me this is how they felt.
Let's look at Lord of the Rings for an example. Consider only Frodo and Sam continuing after the Council of Elrond, with Merry and Pipping going back to the Shire. Imagine Gandalf never returning, but Radagast taking his place. Watch Gimili and Legolas die at the Battle of Helms Deep, but some Rohirim join Aragon afterwards. Golum kills Frodo, so then Sam takes up the ring. Aragorn leads the armies with Faramir and Eowin, while Sam fulfills the destruction of the ring. The important aspects of the story have taken place: the ring is destroyed and Aragorn becomes king, but since not a single character from the beginning remains, would that story have the same epic feel? In my experience (and those of my players), it really doesn't.
Hiya!
Y'see...this is something I don't get. I'm not trying to single you out, Shiroiken, but you made the points so I'm going to use your example as an, uh, example.
Imagine, if you will, The Lord of the Rings as you just described it. The story is about an Evil Ring of Power, created by a super-evil-super-being-of-evil to rule over all the world. Now, you have key characters; Sam, Aragorn, Golum, Nazgul, "the elves", and The One Ring. If you had never known the 'real' LotR story, this one WOULD be epic. The major Characters would still be there...Sam would take the place of Frodo/Sam. The Ring is still the Ring, Aragorn still Aragorn, Nazgul are Nazgul, always hunting for the Ring. Golum is still kicking, etc.
Still epic...just not what we know the story to be.
The same "argument" is used sometimes to justify a Player being given the power to 'veto' the results of a game event if it would "kill/remove" their PC. Kinda like if someone was doing a Star Wars campaign and someone was playing Luke. The Player might make the assumption "Well, I can do anything I want...I can't die. If I die, the entire epic story is ruined". This is the mindset I don't get. A RPG campaign isn't like a recipe for a cake. Baking a cake you can't just substitute floor polish for milk, and switch out plaster for flour. You will not get a cake. But in an RPG? Yes, you CAN switch out Luke for your character Bel'Atha Kurr, the Jedi Apprentice if Luke dies. Will the "normal" Star Wars story, with the whole father/son/daughter thing be the same? Nope! Not even close! Is this bad? Nope! Not even close! In MY opinion...it's BETTER. Because the 'story' unfolds as the Players play the game. That's the draw.
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Anyway...saying "well, if you take Story/Movie XYZ and then change it completely ...you don't have Story/Movie XYZ anymore!", is perfectly valid and true. But assuming that if that happens, it somehow "wrecks" the story/campaign? That I don't get. It didn't "ruin the story"... it just changed it. Often for the better.
^_^
Paul L. Ming