The claim you read from people who believe in GR is that it somehow or other propagates at C.
Again, I really have no clue what you are saying. Gravity exists. I cant explain why, but its measureable and it does not suffer the loss of the time it takes for light to travel between attracting bodies. Just like electrons move at speed of light through magnetic fields, objects move through gravity fields at their respective speeds. The gravity fields do not propogate, though they can change as mass moves around.