But will you put your emotions aside when it's really necessary? For instance they tell you to kill a man for food. And not just any man, let's say he's got cancer and he'll die soon 100%. He also begs people to finish his life and not let him suffer. Imagine the ammount of emotions in your head when you're faced with that bad-case scenario? Would you be able to dismiss them? Would you still do it? But that gets me to the point, that not having emotions is not so bad also. The common sence or your moral standarts come into play. They will let you do something that's not considered good or bad but what is really necessary. Let's look at the example like in the TV-show Scrubs. So doctors there sometimes deal with the patients who have no medical insurance. Now, faced with it what are your emotions: one side we have compassion for another human, on another we have fear for loosing our job. Now the emotions might vary your judgement towards one or another outcome (if you like or dilike the person you're more/less willing to help). Now if we dismiss them the common sense stays and tells you the way you could deal with this issue in a most efficient way. Your clear thinking might even tell you not to help the person because you are being closely watched and get fired if you break the rules hence you won't be able to help anyone anymore.
So my idea is, emotions distract or cloud your judgement (sounds like something a Jedi would say lol), but your cold calculations let you make the best deision.