You actually pretty much nailed it in your response already. A new learning pilot has a tendency to chop the throttle if they get nervous or feel out of control. A positive at mid stick will severely slow the decent and the small amount negative at low stick is just enough to bring the heli down. In other words, it won't come like a rocket back to earth if you chop the stick.
I personally am of the school of thought that you set your pitch how you will fly so for me that's -11, 0, +11 as it's how I learned on my very first heli and allowed me to work on collective skills from the get go but others do learn differently.
Regards,
Brandon Bartolomucci
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