This is a great chest exercise for hypertrophy if you have good motor control. Start with the incline bench set at about 45 degrees, higher than you would normally use for incline bench presses or flyes.
With a slight bend in the elbows, initiate the movement by contracting your pecs. Really try to "open up" the chest.
Don't bring the dumbbells straight down; that will just hit your shoulders. Notice the natural arcing motion of the arms. The dumbbells start at the sides and should stop above the upper chest.
Think you have what it takes to make it in the world of elite sports? Do you have immense talent and ability? Great, but so do a few thousand other guys. Unfortunately, all of these things will only get you so far in this world where good isn't often good enough. At this level you have to be one of the best just to get your foot in the door.