I view the High Post player like a QUARTERBACK in football. This is can be a smart player that has the freedom to make any decision from the Read & React Decision Box.

With this kind of freedom, I also view the High Post Player as a WILD CARD. He/she introduces chaos into the action of the perimeter players. Your perimeter players might only know the first 3 layers of the Read & React, but when you add the WILD CARD at the High Post, defensive situations are created that require more than just “help & recover”.

The actions I am fond of giving the High Post are:

Screen for the passer. The passer is going to cut. It’s a rule in the Read & React. The Quarterback should choose the angle and let the passer perform their cut. Again, the cutter might be a rookie who only knows that they are supposed to basket cut after passing.
Screen for anyone without the ball. This is simply a backscreen – perfectly permissible by anyone in the Decision Box. If the Quarterback sees a good opportunity to send someone without the ball to the goal, it’s a simple as taking a step outside and calling their name!
After any screen, the Quarterback has basically 3 options:Draft the cutter to the goal or at least into the low post.
Shape-up to the perimeter for a Catch-and-Shoot opportunity.
When the cutter uses your screen, immediately set a Ball-Screen. If the Ball-Screen is on the wing, the Quarterback will be rolling to an empty side of the floor – an easy way to be Isolated!
And don’t relegate this High Post Quarterback assignment only to a “Big” player. Give it to your best Catch-And-Shoot player. The defense will be reluctant to switch on the screens and when the Quarterback shapes up to Perimeter, he/she is shooting their shot!

I’ve also gotten really good action by simply using the Best Player as the Quarterback. Whenever and wherever he/she gets the ball in these high post actions, they are usually in the middle one-third of the floor, facing a miniature close-out, with the opportunity to drive, pass, shoot, and generally CREATE!