Vaigai வந்துருச்சு, ஆசையில் ஓடி வந்தேன்

I think u have concentrated more on Fully AC Trains & EOG, while the ongoing discussion was for WAP-5/7 requirement in lieu of hauling capacity vs performance.
(EOG example was to suffice ur query only)
Yes, AC arnt been directly commanded by LOCO, but to run AC Coaches, needs more power (as been nicely explained by Mr. Manoj) for better performance & hence, more AC Coaches, definitely needs better power (and WAP-7 can act better, with better Pick-up, provided Train have too many stop or conjested route)!!
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per RDSO reports only, Loco Performance deppreciates for 24 coach rake, if AC Coaches are been increased!!
Still, WAP-7 has been developed for AC Rake without EOG, y????
Y not WAP-4/5???
Simple, coz it needs more power (Pick-up, power - haulage & AC Control). Still, it has been deveoped, never has been trialed yet!!
@Blogger
WAP-5/7: Shatabdi (8-12 rake) can perform same with any Loco & i have witnessed both with WAP-7. Although BPL Shatabdi can go better with WAP-5, but with 17 coaches, LKO Shatabdi needs WAP-7.
@Blogger
Yes, Punjab Mail do run with WAP-1/4, but WAM series too can be seen, as like in Gondwana Exp!!