I explained this on various places....
enbeffectprepass.fx: Depth of Field shader
EnableDepthOfField: toggles enbeffectprepass.fx on and off
MMGE 3 enbeffectprepass.fx: No DoF, but lighting, skydome, clouds, water and so on.
-> EnableDepthOfField in MMGE 3 doesn't have to do anything with DoF. It basically enables and disables MMGE 3 because everything of MMGE 3 happens in that enbeffectprepass.fx file. No "DoF" -> no MMGE 3, basically.