Sliding of the hips is the obvious problem. You need to have a good swing as to what Els is saying (Don't worry, i'm not saying you have a bad swing) but the fact is, trying this could lead to many faults.

My suggestion, if you're going to be trying this tip, try snapping into the ball earlier using your ''cocked'' wrists on the downswing. You'll need all the power you can get for the clubface to be square at impact.