The selector tag and the screwdriver do the same thing.
How is the cycle time/energy determined with respect to tier and power output?
Is it based on energy and the time changes due to change in output (screwdriver)?
Also, it seems that energy is indeed voided. I put a stack of reeds in bronze squeezers powered by different engines:
LV engine @ 16 KU/t used about 35840EU and ~55 seconds
LV engine @ 24 KU/t used about 55200 EU and ~57 seconds
LV engine @ 32 KU/t used about 33280 EU and ~26 seconds
MV engine @ 64 KU/t used about 133120 EU and ~54 seconds