[jsenn]

This is interesting stuff--thanks for writing it out.

> ...super-Turing computational power.

Could you expand on this? The Wikipedia page claims that the deterministic version can be efficiently simulated by a Turing machine.

The Wikipedia page and page you linked claim that NP problems can be solved in linear time. It does point out the caveat that it would require exponential space, but I think even then something's being swept under the rug. Namely, it assumes that an exponential number of basic computational steps can be performed in a single "time step". In a physical cell (and presumably any other instantiation of this model in the real world), repeated application of a rule like a -> aa would require an exponentially-increasing expenditure of energy, which isn't being taken into account in the analysis.

[fdupress]

Space might be a good enough approximation of energy to not bother?