Understanding of Machine Z-offset and GCODE Global Z-offset in slicer

I am new to the community and I am trying to better understand my settings. The Z-offset on my Lulzbot Workhorse is set to -0.78 mm. In order to get a good first layer and decent prints, I have to set the Global GCODE offset in my slicing software to -0.25 mm. I would prefer to have as few printer specific settings in the slicer software as possible because I am getting a second printer.

Hypothetically, would I be able to sum both of the offsets (-1.03 mm) and set the Lulzbot Z-offset in the firmware to that value and then set the GCODE global offset back to 0.00 mm? I understand there might be some tuning needed, but I just want some verification that I understand what these settings do before I change them.