Frame-Trap in a really simple example is like...
Falco late-D-Airs your shield... You try something out of it... He Shines you and combos...
That's a very basic version that's kind of 'built-in' but not really effective because it's so counter-able/not actually a 'trap' in play, but a trap in mechanics. You can just Shield through it, so what the Falco does AFTER is the 'actual' trap...
Peach can F-Air > Grab you if you Shield the F-Air, because there's enough Shield-Stun that you can't move if you Shield it. That's a little more along the lines of/and the EXTREME of, the ROB example you gave. Shine-Grab after that late-D-Air is another example)
The more effective kind is just a slight hole in pressure (can even be mental pressure) that allows room for the opponent to do something. Usually a conscious move, that they think they can get away with, but you set them up intentionally to be ready for it. A reset with a mix-up to catch them out of their attempt as escaping (catching a Roll or Jump away)/possible mistake (Falco D-Air > Shine > Fading N-Air that you try grabbing but can't)/drop in a combo to reset it (common in things like MvC, akin to catching a Double Jump by letting them go and attacking where you think they're going)/simple baits (stand there for a second not doing anything, even Shield, there's a reason Shield is secretly the best approach in the game)
Stuff like that.
Don't go all crazy attempting to break shields, don't fade back to a raw-neutral if your most recently attempted pressure string didn't crack a defense.
Stay on them, don't give them room to breath, but give them room to act, because you want to hit THEM, NOT their Shield, NOT the air on a whiff, NOT with something you can't convert into something.
You want to KILL THEM!!! lol
Baitin
g with PK Freezes is fine, but more important than what/how/etc your baiting your opponent, is WHY you're doing it.
Why were you baiting with PKF if it got them to commit to something you could punish cleanly, or pressure them for/set-up a mix-up, etc, if all you did was jump away and PKF agian?
Why were you baiting with PKF if it made them approach you, but they did so in a safe way with an attempted PS, or swatting the projectile away, and YOU got baited into approaching?
Why were you baiting with PKF if it made them run away to platform camp or hide on the other side of the stage, and you just stayed in place instead of taking control of the room on-stage?
^That stuff is all that's of value.
Otherwise, I don't care if you're 'baiting' me with PKF or anything else, I'm gonna trick and trap you and if you do something on reaction/habit to it, you're dead, because I like to KILL THEM!!!