Roddick pre-serve stance

[Hewex]

I've been struggling with my serve this year and have trying different things. The other night I decided to try Roddick's stance and pronating my wrist before serving. All of a sudden I picked up more clearance over the net, more pace and spin. I hardly missed a serve. We'll see how it goes in a match today.

So, what do you think of Roddick's stance? Why does it work and have you ever tried it?