From what I have seen of Fedor's fights, it seems to me it will be a lucky punch or kick that dazes him and he gets taken down. I do not think it will be a "skilled" strike so much as a "lucky, skilled" strike.
As for hestating on knocking the crap out of his brother, come on, get real. Machines don't have feelings! Besides, as far as I can tell, the old Soviet Union cloned these two monsters during the cold war as superior fighters. The only emotions I can imagine these two having are hungry, angry, and horny. May God have mercy on your soul if you fight one of these guys on a night when he is angry AND horny.