I think both AB trains are deliberately given slow TT. There are many reasons which i can think of why they did that :
1. So they don't challenge AC trains like Hamsafar, Duronto, Sampark Kranti etc.
2. The targeted audience of AB care more about money than travel time, so IR didn't really felt like making an attacking TT.
3. These trains will...
more... get a huge demand of stoppages going forward, so they can adjust all of them in slow TT.
4. A very fast AB train would catch eye of other zones people who would start demanding AB train on their route.
please wait...Translate to EnglishI think both AB trains are purposely made slow. There are lots of reasons I can think of why they did that:
1. So they don't compete with fancy AC trains like Hamsafar, Duronto, Sampark Kranti, etc.
2. The target audience of AB cares more about money than travel time, so the railway didn't really feel like making a fast schedule.
3. These trains will eventually have a lot of demands for stops, so they can adjust them all with the slow timetable.
4. If an AB train is very fast, people from other areas would notice and start demanding AB trains on their routes.