The window of a train is more entertaining than TV - Kirti Solanki

Prayagraj (WAP7) justifies the slack in TT beetween FTP and ALD
Today 20 Dec morning , when most SF trains in N India are struggling with fog
FTP departure 05:56 (1hr 21min late)
ALD arrival 7:00 (15 min late)
..114km...
more...

covered in flat 64 mins @ 106.7 km/hr!!! ...thus reducing the delay from 1hr 21 min to 15 min in the very last leg of its run.
Herein , lies the secret of PR's comparatively punctual run in NDLS-ALD sector, nothing to do with NCR traffic control's so called preferential treatment.