Fastest is actually Gatiman Express (it is considered as a Shatabdi as per IRCTC) with avg speed of 91 kmph.

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First Shatabdi is the Bhopal Shatabdi followed by Lucknow Shatabdi. There is no way, without data at hand to know which is the most packed Shatabdi.

I would argue the Shatabdi with most slack is 12020 RNC-HWH Shatabdi.With an average falling short of 55 kph mark in this direction and despite running in a 130 kph zone, it has lots of slack. Bokaro - Dhanbad is slack and I had argue, for a 130 kph route, speeds can be managed more at the upcoming stations as well.

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That slack at DHN-BKSC section is due to speed restrictions between Chandrapura and Dhanbad.

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I see. I never understood though why they created a different name for it. Just call it a Shatabdi then. Calling it by a unique name and then subsetting it under the Shatabdi category is basically a looped way to do something.

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