I think a decent two tee drill is setting the front tee with the ball at the top of the ball of the back tee (tees set up about same height and distance apart as above discribed drill). Set tees up with the back tee at contact and front tee approx. 14 inch in front. Hit both balls (back tee first)for a slightly upward path that isn't too much upper cut or isn't flat.
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If you could take that Nike Swoosh and angle it so the straight part is headed slightly down (so rotate it to the right). That is how you should practice hitting off of a tee. Down to behind the ball.