Howrah Rajdhani - At 50, the Handsome King 👑 is still ruling the tracks superbly. - Somanko

Actually 12649/50 Karnataka Sampark Kranti Express via KCG was a Daily Running train Before.
But on that Route route, it did not Served much of Karnataka State.
There was very Much Demand for another good connection to Delhi from People of Belgaum and Hubli as Goa Express used to Run very Overcrowded.
And that time, when Pune Nizamuddin Duronto was not Introduced, People from...
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Pune were also Pressurising Railways to Give a Superfast Connection to Delhi.
And if the train is Routed via Kalyan, it has to Undergo Several Loco Changes, One at Pune from Diesel to Electric, and one at Vadodara from WCAM to WAP.
And Mumbai-Vadodara Route is already oversaturated with premium trains and Daund-Manmad Route is not so saturated line. So I guess Railway did not Run it via BSR.