Jason Day Hits it 375 yards

[Mike Boatright]

http://www.golfdigest.com/gallery/photos-jason-day#20

Notice in one of the stills how much room he has to hit the driver good athlete.

[saevel25]

It's not rocket science. 

First, he has does all the 5 keys really good. 
Second, he has tremendous clubhead speed. He averages 120 MPH with a low of 115 and a high of 125. 
Third, he's playing with a club fitted perfectly for his swing.
Fourth, he optimizes his impact by hitting up on the ball. He's in the top 30 in launch angle and top 10 in the lowest spin rate. This is only accomplished by hitting up on the ball. 

[Mike Boatright]

Well it's isn't easy that's for sure I notice a lot of pros don't have the right elbow room he has and are more stuck on the inside. He makes it look easy with the driver when it's really not that easy or maybe it is does he use the 5 swing key system who is his swing coach?

[Abu3baid]

Well it's isn't easy that's for sure I notice a lot of pros don't have the right elbow room he has and are more stuck on the inside. He makes it look easy with the driver when it's really not that easy or maybe it is does he use the 5 swing key system who is his swing coach?

the five swing keys are not part of a swing system.  It is just 5 things (commonalities) that all good golfers do.  There are different ways to do them as well.. So, for example Jim f. has a strange backswing, but he still achieves all swing keys so no one will tell him to change it..  Everyone has their own intricacies in their swings, but as long as it is functional that's all that's needed. 

[Mike Boatright]

the five swing keys are not part of a swing system.  It is just 5 things (commonalities) that all good golfers do.  There are different ways to do them as well.. So, for example Jim f. has a strange backswing, but he still achieves all swing keys so no one will tell him to change it..  Everyone has their own intricacies in their swings, but as long as it is functional that's all that's needed. 

Oh awesome!

[Mr. Desmond]

Well it's isn't easy that's for sure I notice a lot of pros don't have the right elbow room he has and are more stuck on the inside. He makes it look easy with the driver when it's really not that easy or maybe it is does he use the 5 swing key system who is his swing coach?

I believe his swing coach is his caddie, who is also his father figure. But Jason and Colin Swatton also consult with others -- I saw Jason once with a biomechanical instructor, trying to put less stress on his back. Nice guy, great sense of humor, very positive.