Yes,it's very impractical but actually I think it's kinda like anti faro or something,just somthing KNACK.Hehe I tried it at home but 1 out of 10 can I do it..
actually,It's something like push-off second deal,if you can't do it perfect,then it worth nothing and you can't use it at all.
BUT,IF YOU GUARANTEE YOU CAN DO THIS CHANGE PERFECT EVERY TIME,then there's NO angle sensitive,and you can call it GOD's CHANGE
There's another change that my friend created that kinda similar to Dan&Dave's GOD's change

(At least right hand dose the exact SAME thing

)
http://www.magicvideodepot.com/view.php?a=v&t=11754