How do you realy know your practice swings are "great"? There's no way to know where the face is at impact, where on the club the ball was struck, how solid of contact you made...

All you really can know is simple stuff like tempo, weight shift.

Probably what you need to do is make practice swings with the true intent on hitting a ball (imaginary). Then you will begin to desensitise your head into the "true" practice vs. real swings.