As I have been using the showerhead, for me, using the showercap is essential. The SC makes for some very fast and thick milky vapor. I cap the SH first thing in the draw and remove it mid to late draw to clear the piece and finish it up like
@ichibaneye has pointed out. I also have found whatever quantity you put in the bowl may get completely vaped if you have the lungs, so it is really up to you to use this thing efficiently or not. I can kill almost any size bowl with the SH, it is not that hard. I am putting a thin layer that covers the screen, very nice and very comfortable.