Federer should have gone full brad gilbert on that pattern of play long ago. Actually Dimitrov does that better against Nadal than Fed, which is why he (relatively to his level/ranking) has usually played Nadal well (but lost partly because of lack of believe and other stuff).
What does "full brad Gilbert" mean?
Couldn't Fed just step into the court on those slice out wide serves and take them early before they go too wide?