No, if you look carefully, AGonz first pitch swings at anything on the outer half that looks like it is belt high....and I mean anything...because he is trying to go the other way as often as possible.
I do think this is no longer a secret and pitchers are now trying to get the ball a little farther outside or a little farther low and outside and get Agonz to chase a little bit. The pitch from Hamels that he swung at is more like the kind of pitch he wants so that was not a particularly good pitch from Hamels. However, I have never liked first pitch swinging...it hurts the team effort to drive the opposing pitchers pitch count....it often reduces the opportunity of getting a walk which Ross got right after Agonz, you may be out before you even give yourself a chance to acclimate to the pitchers release point and arm angle and, if you don't put the ball in play you are down in the count right away. The hitter does not even know what is coming at that point so you don't even learn anything from the at bat.
There is nothing sweeter to a pitcher than the sound of Strike 1.