Well, the first incident was today. One cat doesn't seem to really pay attention to the mounts. The other, well, he's totally opposite. He got on the couch, within paw's length of two mounts and decided he needed to sharpen his claws. I was waiting for him to commit the act, he did, and that's when I gave him a swat and blew EXTREMELY loud on a goose call at the same time. What happened after that was pretty much a blur, he almost turned inside out trying to get away. The last I saw was a grey form shooting across the room. We'll see what happens in the next few days.