However, even when done in a more "humane" way slaughtering can still bring about the vice of cruelty. The Ralbag shows us in his third to'elet how the general character of mitzvot can give us even more protection from this vice. I found his approach facinating. I will give my loose translation:
The third [to'elet] is more general, that is, when the mitzva of how to perform this slaughter comes about, it will occur to the Shocheit of the animal that he is not focused [(or) does not have the intention] to kill the animal when he does this action. Rather, his thoughts are upon how to perform this mitzva in the manner in which Hashem commanded. This will be a toelet (beneficial) to being drawn after 'cleaving' to Hashem even while he is doing this -- and to distance himself from the character of cruelty, since he is not focused on slaughtering, only to perform the mitzva in the way that Hashem commanded him.