The incremental speed is correct as per the timings in the official timetable. Between Badnera and Murtajapur, the train is travelling 41 kms in 15 mts. So, evidently, the train must actully arrive at Murtajapur about 20 mts. later than shown in the timetable, or leave Badnera about 20 mts. earlier.
The incremental speed serves as a "sanity check" to see if the timings at the respective stations are roughly correct. Meanwhile, the timings at the 2 stations may be taken with a pinch of salt.
Thanks for the alert.