That's just hit points under a different name. Rolls go against you and you deplete your Edge (or whatever you call it), and when you run out, you pretty much have to stop. The bad guys at this point get away and you try to get them next time, wherever you happen to be at the time.
That's not "seizing victory from the jaws of defeat" by you.
Having PCs constantly win (and making the bad guy run off is better than nothing by quite a lot) and never have any scenes where they can find a small triumph and use it for all its worth doesn't allow for that scene.
Or for prison escapes, which can be pretty cool.
#2 and #3 are inconsistent. Someone already posted the maths.
#2 and #3 are only inconsistent because we think that the math holds up in the real world.
I rolled several d6 yesterday (being a subcommander for someone in a Battlefleet Gothic game).
6d6=/=1, 2, 3, 4, 5, 6 consistently. My first roll of that was 5, 3, 3, 2, 2 as I recall.
Sure, if we roll dice "long enough", probable outcomes will happen.
And if we have infinite monkeys with infinite typewriters, one of them will turn out the works of Ayn Rand.
Several, actually.
But we're not rolling infinite times, and it is just as likely you'll get a 1 when it doesn't matter as when it does.
So, yeah. The math may not support it, but actual dice in play do.
Real question: What do we intend to do about short term healing, defined as something that can be done in the field, in rounds or minutes instead of hours or days (or weeks), in regards to what it can save you from and why we should bother with it?
Trust in the Emperor, but always check your ammunition.