[lupatus]

So, these answers made sense to me at first, but then I thought some more and now they no longer do.

The problem with the usefulness of the Alice-Bob system is that there are two variable pieces of information: c and the classical bits.

Is there a mechanism with which we can control entanglement with qubit c so that only one agreed upon classical bits key, say 00, is the standard and correct key?

This reduces the Alice-Bob system to only having one variable, c, and enables instantaneous communication at a distance.

If Alice is on Earth and Bob on a spaceship, each having their respective qubits, an entanglement control mechanism, and an agreed upon key, then they can entangle other qubits for communication to their hearts' content and receive that information instantaneously.

I think I need to read more about quantum computing now.