Haven't read that theory, but from what I understand, it's been long understood that photons have both particle and wave properties hence the corona effect during a solar eclipse. The belief that the speed of light is a constant could still be preserved, even in the presence of a super-gravitational singularity (black hole) if you accept that the fabric of space time is what is being stretched or compressed. Thus, while the speed of light seems to change relative to the observer, the light is traveling the same speed, simply over a greater distance or smaller distance. It's not that gravity changes the speed of light, but that the rulers get shorter or longer or the clocks run slower or faster due to gravitational influence.... Don't know if this will stand up to Occam's Razor in the long term. Definitely in for more info if you can point me to anything you found interesting on the subject.
I could...but then you or someone else would find some flaw in the theory or science and say it hasn't been proven and blah blah. It doesn't much matter in the end.
I just saw a few articles from Europe about it a little while ago.