If he would have won 1 or 2 already it is a different story, but since he has won none there is no need to assume he would have won some to begin with.
Look at how Fed got his feet wet. 2003 Wimbledon.
Dave had a 5 setter going into the final with Peak Lleyton Hewitt.
Fed got Phil A Poosis in his first final.
How could history have turned for Dave had he won that 2002 Wimbledon and then the 2003 US Open which he was ROBBED of.
When you look at it that way Dave could have had a stellar career, at least on par with Hewitt.
Instead hes got to settle for what history gave him.
Some people got it easier than others.