Warner Miller took a quantum computational point of view on QG: good man. He was analysing lattices built from quantum circuit information flows embedded in spacetimes with Regge calculus. The really beautiful thing was his way of factorising this calculus using Voronoi duals to the lattice, representing matter information content. So pure QG is non-sensical here, which is as it should be physically. The potentials for matter are encoded in the quantum gates. Moreover, it seems one can directly interpret the duality in terms of a principle of quantum general covariance. Miller also mentioned theorems of Cheeger et al which recover curved manifolds from the discrete Regge triangulations, so there is every reason to believe that the continuum theory behaves as desired.