I didn't expect my post about Roddick's "1.5-dimensional game" would generate so much sideline discussion here! As a result of this discussion, I've changed my opinion on Roddick somewhat. Indeed, Rod would've won at least couple more GS if not for Fed, exactly as Fed would've won few more Rolland Garros if not for Rafa.
In that previous post of mine, I had in mind mostly the later years of Roddick's career where his all around game became slower and inefficient (I agree with others it may've been caused by cumulative injuries), and the ridiculous spanking he received from Fed in Basel 2002. But when looked from a larger perspective, Rod's achievements are impressive, as good as they could've been alongside the Big 4 who disallowed him any more.
I didn't like Roddick personally because of his explosive and very silly on court antics: arguing with umps, throwing expletives at them. And for silly reasons because ump judgments he criticized were shown on replay to be very reasonable and sometimes the only ones correct. Almost like Johnny Mac.
BTW, Rod's career was cut short (relatively to his peers, Big4 including) who are still playing, no doubt the result of cumulative injuries mentioned above. It seems like Rod, given he's retired so long ago, would be somewhat older than Fed. But no! He's actually a full 1 year younger: born 30 August 1982 (current age 35).