In my discussions with many staff members of CR Pune Division / SUR Division (during my last 10 years of railfanning at Pune), I have understood following points:
1) Diesel Loco Lobby at Pune / Daund / Kalyan / Solapur is having stronger operational control (compared to OHE / Traction E Lobby).
2) We railfans think too much about speed, power, MPS, loco allocation, DUW (Diesel Under Wires) et al. For IR / CR, its plain BAU (Business As Usual)! For them, till the time train is running (and not stopped, hold up...
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or derailed, etc), everything is OK / All Right!
3) Line Congestion / Platform Availability (especially during evening peak hours) have resulted in DUW for many trains running to / from / via Pune! For example, daily LTT-VSKP Exp / LTT-UBL and weekly LTT-MDU/UBL/NED/KIK/MAS Group of Trains can and should be run with E Locos on LTT-Pune-LTT Section. However, KYN Diesels have taken over these links!
4) There is strong / good / friendly coordination between Diesel Mechanical Group between PUNE / DD / KYN Regions. They have ensured (especially due to DC - AC Conversion in those days) that all newly introduced trains do get D loco only!
5) In the past (7-8 years ago), SBC-JU/GIM/AII Group of Trains also used to get BL WCAM1 Loco on Pune-Ahmedabad Section. In those days, SC-RJT, CBE-RJT, CCT-BVC Group of Trains used to run DUW.
6) It was learnt / understood that PUNE / KYN CR E Traction Group had good / friendly relations with the then WR E Traction Staff. This resulted in WCAM-1 usage from Pune to ADI for CR / SWR Trains and SCR / SR Trains were run DUW as per Disaster Management Plan Principles (say x% of D locos should always be available in E region, etc).
7) Later, with DC-AC Conversion and so called shortage of DC/AC Type locos, all SWR/SCR/SR Trains started running DUW on Pune-ADI Sector and they continue to do so!
8) Only CR Trains are getting KYN WCAM2/2P Locos (which are actually WR / BL ELS Locos) and now WR / NWR Trains are getting BRC AC Locos.
9) With these things prevailing over last few years, now Pune Operations have made it "unwritten" rule that new trains (daily/weekly) will get D Loco only. With at least 3 spare E Locos everyday at Pune, atleast Pune-Karjat Shuttle can be run with E Locos (to save diesel, etc). However, that is wishful thinking from railfans! For IR / CR, such things are not of much concern!
More points to follow soon ..... as per further discussions / posts from other members (if any)!