Well my friends, I've really REALLY been searching for a good CP against R.O.B. that isn't a neutral. Since both Norfair and RC don't work against him, we need something else:
R.O.B primarily relies on horizontal kills. His only vertical killers are usmash, dsmash, nair, and sometimes uair. I've noticed that most of the time the KOs R.O.B. gets will be a horizontal one. This takes out stages where the KO usually is a horizontal kill, like Mario Circuit and Distant Planet (or any stage with runoff edges). My exception, only by theory as of now, is Pipes. I'll get to that later.
Also, he has an amazing recovery. We need a stage where that recovery does not become too much of a problem. Recoveries like his is why we hate stages like Smashville when playing him.
So we need a stage where his recovery is negated. We all know that Link can easily get gimped in stages with large barriers where he can recover and we can't. This rules out the Pokemon Stadiums. We also need a stage where he can't attack from underneath the stage. This rules out Delfino, Halberd, and Brinstar.
Lylat, in my opinion, isn't a great stage for Link. I find the stage tilts to be quite annoying with projectiles. And maneuverability with the platforms is a bit awkward. High ceilings don't matter much, and it's not terribly hard to recover, but still, those stage tilts......I'll leave this one up to discussion.
Corneria is up to discussion. I really have no idea about this stage. Low ceilings, R.O.B.'s laser works well here I think, and that's really all the info I have on it.
Frigate Orpheon - R.O.B. players love this stage. That alone should tell us it's a no-no.
Jungle Japes is like THE camping stage of the game. Avoid this one. I've also heard Green Greens encourages camping. I'll leave that to discussion, I don't have much info on it.
Legan had said to CP castle siege awhile back. Personally, I feel that the statues decay your moves and mess up your projectiles, part 3 is a neutral with tilts, and part 1...he can gimp you right up against the wall underneath the ledge.
We finally get to Luigi's mansion. Short side walls, high ceiling, dsmash spam on the first floor, R.O.B.'s laser does VERY well inside the mansion. It's not a good idea to go here.
So that leaves us with:
Castle Siege - ???
Delfino
Halberd
Lylat Cruise - ???
Pokémon Stadium 1
Brinstar
Corneria - ???
Distant Planet
Frigate Orpheon
Green Hill Zone
Jungle Japes
Luigi's Mansion
Norfair
Pictochat
Pirate Ship
Pokémon Stadium 2
Rainbow Cruise
Yoshi's Island (Pipes)
Mario Circuit
Green Greens - ???
So my thoughts on the CPs against R.O.B. I've been experimenting with Green Hill Zone for a bit, and to be honest, I've found it quite successful so far. The ground decays your moves, yes, but the valley portion SO good for SH aerials. Also, Link's projectiles make getting the checkpoint a lot easier. Always remember to hit that checkpoint, it really can work wonders. The checkpoint is the blue bumper, for those of you who aren't Sonic fans. Plus, the angles of the ground mess up R.O.B.'s projectiles. There's not really a place where he can camp you. The ground will decay his dsmash as well. Fast falling on the sides will increase your speed down to the bottom too, because Link just slides. The only downside is that Link's dair is negated, since the ceiling is very high.
Pipes - another stage where I think the tight spaces and low ceilings are not good for R.O.B. Again, I think the angles would mess with R.O.B.'s projectiles, and a low ceiling is good for Link's dair. Plus, the chance of getting gimped is almost zero. Nearly every KO on you would have to be a direct hit.
Pirate ship - theoretically, the water stops all gimps from happening. However, being in the water also increases your chances of getting spiked. I'm not sure if R.O.B. can use his upb right out of the water, but if he can't and you're both in the water. feel free to use the dair, there's no landing lag. The ceiling isn't terribly high either, and the "falling ship" part is a great place to constantly use the dair. I know I keep stressing using the dair, but I just feel like that's the best move to KO R.O.B. Don't think I'm forgetting about other moves though.
If you feel different about anything I've said, would like to correct me or dispute me, please feel free to go ahead. I've been wanting to find a good stage against R.O.B. for a long time.