[AdmSmith]

In Einstein's General Theory of Gravity the speed of gravity is assumed to be equal to the speed of light. If it is found to be different then his theory must be changed for something better. That is evolution!

[PonyTailGuy]

But is that really how science works? Not every proposition in a theory exposes the theory to extinction by disproof. Those in the HARD CORE of the theory certainly do, but these are the cardinal propositions in the theory, not auxiliary laws, models, etc.

For example, the field of genetics is based on the cardinal rules governing of combinations of genetic "factors". Should someone find that alleles do not in fact combine in accordance with those rules, it's bye bye to Mendel.

But the precise mechanism of the joining of alleles does not have to be hard-wired in genetic theory. Someone can find that a commonly held view of crossover and mutation is not accurate, and the hard core of Mendel's theory would still hold.

One must distinguish between these cardinal, essential propositions in a theory, and the outer ring of ad-hoc or weak principles that merely support the theory or explain its mechanisms in some cases.

This is why I framed my question in terms of the relative place of the speed of gravity proposition in the general theory.