Very simply, this is the cadence best utilized for the Triple Option Offense.Down, Ready, Sethut
The ball is snapped on the “S” in sethut.
In 2010, Navy added the word “Down” to eliminate the foot stomp on Rocket and Midline Lead.
One thing about the Triple Option Offense–you WANT them to blitz and you WANT them to penetrate, because you veer right past this. So yes, you always go on the same cadence; however, when utilizing “Freeze” and by adding the words LEFT or RIGHT- the A-back to that side goes in tail motion and freezes on the “s” in set, returns to the initial position, Quarterback calls the play, and then the play is executed.
This is commonly known as a double count.
The article on how to best utilize the FREEZE concept to dominate stemming defenses can be found here.