I thought this was a very interesting concept. His description of gravity being a flow of particles makes more sense than an attractive force.
The only problem I had with it is explaining the dual tides here on earth. The tide between the moon and the earth is easy enough to understand. However, the bulge on the opposite side of the earth shouldn't be there in the face of a full flow of Superlight.
The only way I could think to explain it was with a lensing effect created by the earth. If the earth acted as a Superlight lens, it could focus the flow from around the moon so it converges on the opposite side of the earth and causes the bulge.
Another theory is some sort of a Superlight standing wave created between the moon and the earth.
The wayyyy out theory is that there is another moon, perhaps in another dimension, exactly opposite our moon in orbit and having an effect on the tides. A phantom moon could go far in explaining all the unaccounted for dark matter in the universe.