Take a look at Mathew's image of the 'endless belt'
The aiming point is 'where you point the belt'
It is where you are sending the force so that the 'circle' is positioned properly, to ENSURE lag at impact, to ensure you haven't 'thrown away' force.
In a nutshell, pick a spot in front of the ball, drive your hands there until both arms are straight - experiment with how far forward that spot is, anywhere from the ball, to several feet in front of the ball (about 2-3 is a good general area) There are other variables than come into play, keep that 'circle' in mind
Edz,
Good post. Could you expand on positioning the Belt? I assume you want the impact interval to occur during the pulley section of the belt?