It really doesn't work as well as it should, the enemy takes the damage but not the recoil which makes stomping very dangerous as when you shoot their legs off and they are on the ground, when stomping on them during mid attack, it does not interrupt their attack. (n4g.com)
Mario and Luigi are able to stop the lethal shots by stomping on them in mid-air; they can also be dodged relatively easily. (mariowiki.com)
I still can't believe people defend him when he's a terrible person that ruined Luiz's leg, after stomping on him in 13/14 at the Etihad (sbnation.com)