Its all about hotel load. Complete AC Rake or HS/AP/AT (Akal Takht)/Punjab-LKO-GUJ Mail etc with high AC count need dual EOG at peak hours, in case HOG disfunctions.
Jansadharan/Karnataka/Ziyarat/Gomti etc with low AC count can survive with one EOG and surely can be replaced with 1 LHB SLR to allow Disabled/Woman traveler as like in ICF Rake!!