Holy necro thread, Batman!......
Pull away is only one of several methods for shooting sporting clays.
Per Gil and Vicki Ash - two great instructors, you focus 95% on the front edge of the bird and maybe 5% on the barrel in your periphery; otherwise you start to focus only on the space between the target. The more you are aware of the lead and not the target, the more you focus on the lead and not the target and the more you miss.
You start by determining your hold point, insertion point and break point. You work from back to front - in other words, you start where you want the bird to break - that is the point where you see the target the clearest - and then work back about 1/3 of the way towards the machine. Keep your eyes on the target, coming off the machine if you can see it, while your muzzles are at your insertion point on the target flight line. As the target crosses that insertion point, you are moving the gun to the target. When you catch the target (keeping your focus ON the target), you pull away as you fire