Rory's swing flatter?

[tongzilla]

I noticed he's swinging even flatter than before during this year's Masters...
He's driving it better than ever though. Just looks a bit flat to me.

 

[spktho]

He's always had his lead arm going pretty much straight across his chest in line with his shoulders in the back swing, then lets the club drop to start the downswing. He is playing very well.