only problem is getting out, I'm sure you can just fight the chozo ghost out of bounds and bomb the slot that lets you leave before warping back inbounds but i havent tested it yet
yeah without floaty jump. there's a description on m2k2 (no video though).
non-FJ training chamber SW was one of very few SWs I was never able to do. flamancipator claimed it could be done, and I think I even asked sparky to use moon jump to figure out where the lowest part of the ceiling is, but I never got out, and I've never seen it done without FJ.
I think it can be done if a ghost pushes you out with a shot of what ever it is they shoot at you, but I dont think you can get it without using a ghost or FJ
From the video Juliano posted it looks like you might be able to pop yourself up over the edge with a twisting R jump. For some reason R jumps carry more "momentum" and will sometimes allow you to slide up and over ledges like that one. I might give it a try once my Wii gets back from repair (DREs). Those Wii lasers just aren't made for shit.