Flacid Pumping

I am wondering if it is possible to still gain if you pump flacid, or is this not recommended. I am new to pumping, and I am doing one /10 minute set everyday at 5/HG pressure, ….as I am concerned about over pumping, and injuring my penis.

My experience was, whether I started flaccid or erect, going into the tube, once the pressure was applied, I was fully expanded, and that, to me, is the point of vacuum pumping.