This is also referred to, on various railroads as rules covering :
"Centered and Set"
"Red Zone"
"In Between"
All mean basically the same thing, just each railroad has their own way of doing things.
I've even heard of railroads where the employee will call to :"Enter Red Zone" or "Go Between", and the engineer will replay "Centered and Set", and stick both hands out the window, holding the reverser handle so the employee can SEE it.
It's all for safety, and frankly while it takes more time, it's worth it.
If you're in there, you do NOT want that train to move!
- litz