Knowing that I'm just performing necromancy on a dead horse so that I can beat it to death again, I thought I'd just pop back in here to post that I've recently discovered that you can replicate the Palps vs the Jedi Masters scene from Episode III using the SWSE rules. All you need is enough Destiny Points and stuff like the Triple Crit feat. Here's how it works:
Palptine charges Saesee Tiin and uses a Destiny Point to auto-crit (dealing triple damage with his lightsaber - and undoubtedly rolling very well on his damage dice in the process). He then spends another Destiny Point to act again, attacking both Agen Kolar and Kit Fisto with Double Attack, spending two more Destiny Points to auto-crit on both of them as well (again rolling well for damage, which is again tripled). While Kolar goes down, Fisto survives the initial attack, but on the following round, Palpatine rolls a natural 20 and crits him again, taking him out.
Bear in mind that there are no restrictions on the number of Destiny Points you can spend in one round other than to change your initiative order (which can only be done once per round post-errata).
Now, you can certainly make a case for Palpatine's damage output not being high enough to take out the Jedi Masters in one hit, even with the Triple Crit feat. If you use the published stats for Palpatine, Tiin and Fisto (Kolar was never officially statted for SWSE), that's exactly the problem. Palpatine can do 2d8+10x3 on a critical hit. The maximum is 78. Fisto has 122 hp, while Tiin has 144.
However, nowhere does it say you have to use the "official" statblocks. Most of them are junk anyway. You could make Palpatine a bit tougher, or the Jedi Masters a bit weaker (perhaps by giving them some nonheroic levels rather than all heroic levels, which would give them fewer hit points; you could also give Tiin, Kolar and Fisto no Destiny Points to represent that they'd exhausted themselves during the Clone Wars; who knows, maybe they've even got some persistent condition track penalties as well) and still represent that scene using RAW.
And thus, spinning it around, you could have a single 20th level Jedi Master take out a gaggle of Sith Lords each in one hit using the same Triple Crit + Destiny Points + whatever else you can think of that might help combo.
So it can be done without any GM handwaving or plot fiat. All it would require is that the characters in question be built in such a way as to make it possible, but that can be done by staying well within the RAW (if not with the exact official SWSE statblocks for those given characters).
EDIT: Re-reading some of the responses on the topic above, it seems to me like some people's issue has less to do with being unable to replicate certain scenes using the SWSE rules in general but rather being unable to replicate them using the official statblocks for certain movie characters. I'll admit that you can't replicate certain scenes using the official statblocks, but as I said before, most of those statblocks are a waste of space anyway. It is entirely possible to build entirely RAW versions of the movie characters that can be used to replicate those scenes without resorting to house rules or handwaving of any kind.
Just sayin' ...