BCT Rajdhani runs mainly on plain land. apart from Golden Bridge & Tapi Bridge, all other bridges on NDLS-BCT route are modified. There is not a ghat section in NDLS-Mumbai Route. Whereas in HWH-NDLS route, Yamuna Bridge after Allahabad & Falgu Bridge after Gaya have speed restriction, there is a ghat section between Koderma & Gaya having speed limit & constrains. Seeing all this aspect, HWH Rajdhani still maintains 85 kph avg speed. HWH Rajdhani is legacy, The God of IR, BCT Rajdhani is the King of IR, not GOD of IR.
The success of HWH Rajdhani from 1969-72 prompted IR to start more Rajdhani Services from 1972 & BCT Rajdhani started in 1972.