That is what i am saying. Running the DD behind Karnavati is a waste. Instead the coaches of the DD should be used on the high demand Ahmedabad Shatabdi & ofcourse if the Shatabdi runs on Sunday then it will be the most profitable train on the route.
I used to run up & Down from Surat for a couple of years & the Karnavati in the morning and Shatabdi in the evening were the most popular trains on the route. Since the DD does not run on Sunday, those coaches could be used on the Shatabdi timings & everyone would be happy.