I have 200 washers to cut from 4.55mm Victorian Mountain Ash timber. Not the most exciting job! I decided to do some testing to get the settings that would give the most efficient cutting without manual intervention to finish off the cutting. (Sometimes I use a scalpel to complete cutting as required.)
Cutting on the E2 - 150mm/min 100% power x 4 passes sees the washers cleanly drop out of the material. Pretty good.
I tried running two passes at normal focal setting and dropping the Z axis by 2mm then running two more passes. It was no where near cutting through the material. So, leaving the focus setting at the optimum calculated by initial focus tests, seems the best option for cutting efficiency.