Many years ago, the Caterpillar Tractor Company ran a series of ads with a tagline that said: "There are no easy answers. There are only intelligent choices." That's true for supervision.
Supervision is an art. You can use some science to help do it better. You can follow the Ring Lardner Principle and narrow the odds. But in the end, you are going to make intelligent choices, act on them and then see what happens and adjust.
What that means is that you've got to master the arts of follow-up and adjustment. A lot of the art of great supervision involves following up to make sure what you have agreed will get done is, in fact, getting done.
The other way that the Caterpillar Tractor Principle works is that you very often will not have a clear choice among alternatives. Don't let that slow you down. Don't let it stop you from making a decision. Don't let it stop you from acting.
To make the Caterpillar Tractor Principle work for you in supervision, don't look for the easy answer. Instead sort out your intelligent choices and take action. Then follow-up and adjust if you need to.