[EricH]

And, to add to what Chris is saying, the official definition is "above the plane". The question is, is a robot that is on top of the platform above the plane? I can think of a situation (admittedly, it's kind of improbable) where it could be ruled to not be, despite having nothing hanging down, if the GDC doesn't come out and say that being on top of the platform is above the plane.

The situation I'm thinking of? The platform deforms, and a robot's wheels wind up in a dip that goes below the normal level. Like I say, that's improbable, but it could happen.