It is something you just have to learn to feel. I have seen them plant their back foot and still look like they are dropping their shoulder.
Sounds like what you are doing is a leg yield with a half halt then turning. This works but you are changing directions. With a side pass you are not. You side pass the direction you wish to turn.
-I'm so busy... I don't know if I found a rope or lost my horse.
-An Armed Man is a Citizen an unarmed man is a subject.
-Where ever free speech is stifled Tyranny will reign.