Shabdbhedi Express: गति इसकी शब्दों को भेदती है, पूरब को पूर्वांचल से जोड़ती है - Dr. Abhishek Rai

Answers to your points :-
1. I'm aware of it. Hence the stoppage time was reduced to 10 min long time back. However, the overall schedule did not change.
2. Yes, WAPx locos are fit for higher speeds (130+ km/h). But were they really running at that speed?
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The MPS for the Rajdhanis was increased recently.
Another factor which must be considered is the inter-stoppage distance. BPL Shatabdi stops at 7 places between NDLS and BPL (702.5 km).
Average inter stoppage distance = 100.35 km
BCT Raj stops at 5 places between BCT and NDLS (1385.6 km).
Average inter stoppage distance = 277.12 km
In terms of priority, both are kings!
^ Clearly, the Raj can cruise at MPS for a longer distance unlike Shatabdi, which has to stop after every 100 km on an avg. Hence, the average speed will be higher.
BTW, Shatabdi's avg speed was 90 some yrs back. Thanks to politics, it's all ruined!