Schwarz's curse is actually... A disability...!
When he's at his best, he fools himself into thinking that's how he is. He feels normal, and "normal" must be sustainable right?
So he builds his life around what he can do in that normal state- only for it to come crashing down when his curse rears its head.
(but really, it never went away. It was always going to flare up. so why did he choose to do something that was only possible if he didn't have it at all? of course, he can't help it)
So while Schneeb is at this dead end with nowhere to go up or down, Schwarz is constantly climbing higher and falling lower. Maybe it's not that different when I see it like that.