Sorry no need to get your panties in a bunch.
Yikes too much time spent on these boards made me reply to your earlier post like a Smash64 boards veteran. That is out of character for me
Consider panties unbunched
STUFF --> I don't think that's possible on SSB64.
It is possible, actually, and not just in theory, I and others have done it... and yes, it can help you escape wall infinites, among many other more important things. I highly recommend checking out ant-d's thread: "Directional Influence - A Summary"
Saving yourself from direct KO hits like in Melee or Brawl isn't really there, but say a smash hits you near the ledge, if you DI into the ledge and bounce, that just might save you... anyway check out that thread, should be informative.