Yeah, glad they address the scaling thing. My initial thought with jumping is that, you can't have your cake and eat it too, in regards to physics.
Either you scale down in a way that works with physics, and die instantly. Or you scale down 'magically', and imo you don't get to reap the benefits of stuff like 'extra' strength and other square-cube-law changes. (though, I guess if you are just saying 'it's magic', you can come up with any number of justifications for keeping that stuff)