You can't even compare Harrison to DY, he has shown that he is for real and has more promise than DY ever will. First off, before he was even pro he won his first tour level match at 15, beating a clay court specialist on clay. Not to diminish DY's junior achievements, but while DY was winning junior events, Harrison was beating top 100 pro men, on their best surface, so he set himself apart right there.
As for his WCs, I've already said there is nothing wrong with getting them your first few years on tour, but beyond that is too much, and Harrison's ranking is high enough that soon he won't be needing WC's, and certainly won't need one for the US Open, he's top 80 currently. And the WC's he gets he makes the most out of, winning multiple matches at IW, beating Raonic, who was as hot as anyone, other than Djoker, and giving Fed a decent match, he went deep in Atlanta, and LA and qualifying, rather than getting WC's into all the majors this year, his Aussie WC was one he earned by winning the playoff, so no Harrison in no way has WC's to thank for his place on tour, he's showing that he could be the next great American player by winning plenty of matches against quality opponents and giving guys at the top problems as well.
You are really reaching when you try and compare Harrison and DY.
And on DY doing better this year, he has been earning his way a little more, better late than never I guess, but my original comment was referencing his entire career, not just this year.
This year, Donald has beat both Murray who is ranked, what #5? And Melzer, who might have fallen out of the top 10 but was ranked #7 recently.
Harrison hasn't beaten anybody that good.
So let's cool it with the Harrison talk until he's beat similar opponents.