What separates a good one-step from a bad one-step?

[Kung Fu Wang]

One should aim to control the fight from the beginning,

Agree with you 100% on this. In a fight, if you drag your opponent's arm and run toward his back. You can force him to either resist against you or yield into you. No matter your opponent is a boxer, MT guy, Karate guy, BJJ guy, or ..., he may not be used to this fighting strategy. That can be your advantage.

You may be responding to a feint.

I like to use feint. That's why I don't like to deal with feint. I don't like to fall into my opponent's trap.