Can you explain why edgehogging has more depth than ledge trumping?
Basically, edgehogging is a part of a complicated rock-paper-scissors loop, and edge trumping lacks most of that dynamic. Edgehogging basically means, you can only hold the ledge for a certain period of time maximum, the combination of your ledge invincibility time, and your roll animation. So your goal is to maximize this coverage by grabbing the ledge as late as possible, and rolling right as they try to get up onto the ledge.
This is complicated because many characters have stalling options that can wait out your ledge invincibility time, or your roll. So you might press the button too early, because you expect the opponent to go up right then, but in reality, they had another jump or alternative air stall option left, so they can wait out your roll. You essentially need to predict the timing they’ll return to the stage. Early, normal, or late. On the early side, frequently they’ll attempt to directly attack you as they’re coming up, so you can’t get down to the ledge in time at all. This whole thing is a timing mixup.
It gets more complicated when you factor in that most of the time, it’s possible to return to the stage, you’re not forced to grab the ledge low. So then the mixup is, can they make it back to the stage or not? Will they try to make it back to the stage or not? If there’s a possibility of them making it back to the stage, then if you roll on-stage, then you’ll sacrifice the advantage time you need to send them back off again. So there’s this element of valuation: How far can my opponent go in their recovery? Are they being forced to recover low at all?
Then there’s the fact that you have two other ledge guard options you could be doing. Onstage edgeguards, or offstage edgeguards. These can be more effective than ledgehogging depending on the situation. Offstage edgeguards can mean you don’t need to guess about their recovery at all.
On-stage edge guards are particularly good in melee because melee has the sweet spot, and smash 4 has magnet hands. In Melee, to actually recover, you have this tiny space where you can grab the ledge and none of your body pokes up over the edge of the stage, so someone on-stage can’t hit you. In smash 4, you have magnet hands that catch the ledge if you’re anywhere in the vicinity of it, so on-stage edgeguards are useless. Doing an on-stage edgeguard takes less time than trying to set up the right edgehog, but it’s usually more of a crapshoot, since you’re relying on your opponent to mess up. It’s possible to use a falling aerial that pokes down into the sweetspot zone to hit your opponent, but this is again a timing mixup.
Also worth noting is that PM reduced the ledge occupancy time of the roll, which I think is appropriate. It was just a little too good in melee, allowing you to cover both timing options frequently, where in PM it can only feasibly cover 1 usually.
Marth’s Side B is an air stall, so I use this all the time to sneak up onto ledge after someone rolls.