
Originally Posted by
Primalinstinct
Yes, you do use more back on decline and you do not isolate the pecs as well. However you are focusing on the lower part of the chest and that helps separate and define the chest from the lower abs.
I interpet my chest in three parts when I set up a workout routine:
Upper
Middle
Lower
Just look at any of Arnold's classic most muscular posses. Nobody displayed pectoral separation better than him. Notice the definite line between his upper and lower chest. It's like a borderline on any map.
Isolate, mix it up, keep it fresh, shock your muscles. Chances are you will last longer and get better results.