Loco plays an imp role in planning a travel time and of course SHATABDI is given an utmost priority in any given route.So I feel one has to keep the loco in mind while planning a TT...Why cant we plan trains with shortest time possible..We guys know sathavahana dont require 05 50 mins with p7 loco from BZA-SC but with advancements also the time is like that only...Common guys...IR is advancing..if we are like this only our grand children also travel in the same trains taking 5 hrs 50 mins ...