everyones body is different...for example some have wide shoulder girdles, some narrow. some have long arms, some short. the triceps are much weaker than the pecs, therefore they will almost always fail first. the width of your shoulders , length of your arms also factor into the equation. without knowing your physical traits, my first suggestion would be to pre-exhaust. trying a new technique will not hurt at all, you will probably be pleasantly surprised! supersetting benches and flies is another way to raise the intensity level of your workouts without trying to push too much weight. it's fairly obvious(to me anyways) that the tris are doing most of the work here, because you arent feeling anything in your chest......give it a try......if it doesn't work for you, find another idea....there are lots.