Comment by gizmo686

Gravitational waves have a similar effect of sapping the kinetic energy of orbiting black holes. Instead of heating the black holes, the energy is emitted as gravitational radiation. Having said that, now that we have actual observations of the gravitational radiation emmited from merging black holes, we can be pretty confident in our understanding of the magnitude of this energy loss. And that understanding is that it does not become significant until well into the last parsec.