I am not sure how closely 4E combat will resemble Star Wars Saga, but a few insights form having run a a handful of sessions of Saga, based on some comments here.
1) Save or die is bad because it bypasses the hit point system.
Ok, but so does the condition track. You can have plenty of hp left but knocked down to the dying condition on the condition track. The whole system of a condition track bypasses the hp system, so if it is a valid reason (i.e. the hit point system should be sacrosanct for determining if a character is damaged or dies) for not using save vs. die, it should also preclude using any kind of subsystem that bypases it such as a condition track.
2) In Saga combat, characters are going to take a whole heck of a lot more hp damage in a combat. Even with characters starting with 3 x HD worth of hit points, I had characters dipping into negative hp every combat, even against mooks.
As an observation, abilitis need to be balanced per encoutner with a system like Star Wars Saga combat. Characters who do not go all out in the encounter may not make it through it. If they hold back something in reserve because it might be needed later, they may well not make it to later. Characters taking hp damage pretty quickly, and even mooks with something like Coordinated attack like the stormtroopers get, can do some severe damage to party members, or large chunks of th party firing on an area rather than an individual. Hits the exceed the damage threshhold slide people down the condition track making them easier ot hit late rint he combat, and the lethality potential begins to spiral upwards fast. Force points, destiny points, etc. all got used up pretty fast to help characters survive encounters, let alone win.
Granted, we have not seen how 1stlevel hit points will scale against weapon damage in 4E combat, and w edo not know if the condition track and damage threshholds are part of the combat system. Still I have found Saga combat far deadlier and more lethal to PC's than traditional 3.x combat ever was. Add in expanded crits form spells and such, and I am not sure you will need Save or die effects tomake things deadly. I see a lot of PCs dying form dice rolls, those generated in combat rather than saving throws.
3) And not to be flip, but if there are no longer any saving throws, but static defenses instead, can their really be a save or die effect? Saving throws are reactive to something bad happening to the character. It happens then the character reacts to see if it happens. With static defenses, the attacker has to roll againt the defense to see if it even happens. There is no save at all. Sith lord trying to mind control you, he roll an atttack against your will defense ad adds all his modifiers. If he beats your defense, you are mind controlled. I expect that is how things like domination will work too, so technically there is no save vs. condition or save vs. anyything, just if the attack is successful.
The effect is that the action becomes much mor eactive than reactive. The acter does the dice rolling, not the target.
2a) No character should die because of a bad die roll?
Going back to this for a second. Come on, really? In a game where every success or failure is based on dice rolls, bad things shouldn't happen on a dice roll?
Even if your argument is the story should be supreme, I can't see it. Well in a sense I agree, but a story needs dramatic tension to even be a story. Predestination is not a story. Creating a story where the PCs cannot lose is as much a railroad as taking the decisions out of their hand. No chance of failure and/or death means there is no consequences for the choices they make, and therefore not much of a story. There is no point in them making choices if the choices are meaningless.
Losing characters is not fun. So is going through something that has a predetermined outcome. If I already know what is going to happen, that my character will win no matter what I do, then how is it fun. I beat it, yay, so what, it was never in question.
If the character is afraid to die, it has a choice whether or not to put itself in a position where it can die. Taking on a powerful wizard means the character chose to put itself in a position where it is at risk of dying. Don;t want to take ont he wizard, make a choice ot overcome the obstacle another way. Enter the dungeon? You are choosing to put yourself at risk. Adventure is risk. Risk results in excitement. The outcome of the dice create tension n the game. Sometimes you do everythign righ tand still fail. Other times you get lucky even when you make an error in judgement. That is the essence of risk, and risk is at the heart of adventure. Since from my point of view, adventure is at the heart of D&D, risk should be at the heart of the game. Others may have a different view, but I find predicatable things boring. If I want predictable, I will watch primetime TV. Everything is nice, safe, and predictable there.
As for 4E as a whole, so far I like a lot of the stated goals of what the designers have put forwards, though for me it is going ot be a mtter of how it is executed. SinceI really won;t know how it is executed until I see the final version of the rules in print, I have ot reserve judgement until then. If the execution can achieve the stated goals of streamlined gameplay with a larger sweetspot and still retain options for players and the heart of D&D's adventure game soul, then I am ok woth changes to the details and latering sacred cows. However, if the execution falls short, no amount of sacred cows retained or slaughter will make it a game that will be fun for me to run and play. It's a matter of show me the execution baby! If it does, great. If it doesn;t oh well, I have been playing since '81 and I will find some way to keep playing that is fun for me and my group of fellow players. I am not going to sweat the small stuff until a clearer picture of the big picture becomes available.
-M