The torch has been passed to Opus, and I'd say we're in business! Still 200+ fps.
As it turns out the reason my previous attempt had so much trouble with the sphere primitives is that they aren't supported by my python bindings. Fable just implemented sphere intersection off the raytracing cores.
Video
Oops! All Paperclips
Cool. Still 700 fps. I'm curious to see how long it takes to rebuild the acceleration structure, would be sweet to get this in realtime with Fluoddicles