Dear Kent,
Yours is the most interesting essay I have read so far on this site.
It seems to me that the signalling problem will lead us to the next step in physics. I am inclined to think that quantum mechanics in fact describes a digital communication network. Shannon's theory of communication tells us that we avoid error by quantizing messages, that is by making them as far apart as possible in message space so that the probability of their confusion is negligible. This would seem to explain the fact of quantization.
Shannon's theory also explains the delay in error defeating communications, since the packetizing system must wait for the source to emit a certain number of symbols before it can construct a packet. We might associate 'the universal minimum error proofing delay' with the velocity of light, light speed representing the fastest communication algorithm in the universe.
In situations, where error is not a problem, the error proofing delay is unnecessary and so we might get superluminal communication.
A computer communication network is a digital, logical system, and it seems to me that such a system has a property we might call logical continuity (like a proof or the execution of a Turing machine) , which I feel is logically prior to the geometrical community that physicists struggle so hard to preserve.
Finally, the network approach might lead us to the idea that gravitation is not quantized since, like an ideal power distribution network, it is operating at zero entropy, not transmitting any information, therefore has no possibility of error and so quantization or packetization for error prevention is unnecessary.