You are restating my paradox, which I stated about 36 yrs ago, and challenges the very existence of black holes. Because, if they attract by use of gravity waves, then surely the waves can't get out of the hole - and so the black hole will never be felt by anyone outside!
I have asked astronomers over the years if the paradox has been resolved and the only answer I ever get is that when they find the black holes I will be proved wrong!
So if the new work of Fomalont and Kopeikin find that the waves are indeed affected by gravity fields, then they are a step towards proving me right.
Would love to get e-mail on subject: shannon@saad.org.il