A slightly off topic question: Have you ever heard of Joao Magueijo and the theory that light was faster in the early universe? Makes me wonder if true, would the speed of gravity waves also be faster?
I have never investigated his theory (and I can't thus answer your question). One alternative to standard physics. His theory is however testable, but I don't know the status. I guess: still pending (as I can't find anything new with this respect) :)
Also makes me wonder if the speed of light and the speed of gravity waves have been compared yet? Any cataclysmic events that have been picked off by LIGO as well as by optical telescopes?
Yes they did, thanks to the neutron star merger event for which both gravitational and electromagnetic waves have been observed. The speed match to an amazing level of precision.