I've seen FAA play many times and from the get-go I kind of had this feeling, but it's becoming more apparent as time goes on. He reminds me of Roddick in his later stage, actually. It seems like he's trying very hard to muscle through the ball, but he's not using that power efficiently so it doesn't translate into a fast or powerful shot. This is ironic as he's being coached by Toni Nadal, and Rafa sure knows how to generate a ton of power into his shots.
Just look at the highlights from his match against Altmaier:
It's like he's really trying to use his power and I'm sure he's strong. It's not a matter of physical strength. He's just not using that power efficiently. You've got people who aren't that muscular at all (Kyrgios, Eubanks, Rosol come to mind) that can easily hit huge shots. That is what he needs to work on. It's not even so much tactics, it's just this. His average baseline shot is too weak. When he hits an approach shot to go to the net, it's too weak. And it's the same when he tries to hit a winner, it's just weaker than other players' finishing shots, so they often still get to it.
Just look at the highlights from his match against Altmaier:
It's like he's really trying to use his power and I'm sure he's strong. It's not a matter of physical strength. He's just not using that power efficiently. You've got people who aren't that muscular at all (Kyrgios, Eubanks, Rosol come to mind) that can easily hit huge shots. That is what he needs to work on. It's not even so much tactics, it's just this. His average baseline shot is too weak. When he hits an approach shot to go to the net, it's too weak. And it's the same when he tries to hit a winner, it's just weaker than other players' finishing shots, so they often still get to it.