So I used to be really big into the whole mind-muscle connection thing....that I need to feel and be aware of a muscle contracting to get the maximum benefit. I still believe it to some extent, but realized I may have been misapplying it to my compound lifts. Now rather than benching and thinking, "Okay, I need to get a good stretch of my pecs, delts, and triceps", I've focused just on putting weight on the bar and maximizing the poundage. Basically, I stopped thinking about bench press as a chest exercise and instead thought of it as a method of moving weight around and as a result, have gotten a bigger bench and a bigger chest.
Cliffs: I stopped benching to get a bigger chest and instead started benching to get a bigger bench.
In addition, I've dropped the reps and upped the poundage on my dumbbell flyes. While before I was doing sets of 10-12, I dropped it down to the 4-8 range and have had awesome results. I consider dumbbell flyes to be my primary chest movement now and really attribute most of my growth to focusing on them.