Another thing to keep in mind is no-impact landing on the ledge. The strength of this option comes from the near overlap of the height at which Samus's ledge grab collision bubble collides with the ledge's grab collision bubble, and the height where her landing detection collision bubble collides with the stage's surface. They're close enough that if you're jumping at the right height it is impossible to know whether you're going to land on stage and immediately attack, or if you're going to re-grab the ledge. If they think you're going to land and attack, they can try to poke pre-emptively, which leaves them vulnerable if you grab the ledge and immediately ledge-dash. But if they think you're going to re-grab the ledge and they wait, and you land, they can't react to your attack.
Now, this mix-up does necessitate you poking up fairly far above the ledge, so if they read that you're going to go for it, they can poke you out of it. The very question of whether you're going for this mix-up needs to be a mix-up. Don't always go for it. Jump from lower for quicker ledge stalls to keep them guessing.
