OK, so his single best Force feat is his temple busting, which was done while charged on a nexus. I buy that RoT Bane > nexus PoD Bane, but he'd still need some time to charge his attack, and even then it does not seem to be something he can just replicate on a dare; it's like a really big peak outburst (as he doesn't do it ever again). I don't have the exact dimensions of the Temple feat but I'm not sure if that's enough to redirect the star destroyer, I'd have to do the calcs.