Who says South India does not have Gatimaan. It is called Vaigai Express. - Thamizh Maran

ECR can be basically classified into 2 areas :-
1. The Have.
2. The Have-nots.
DDU/DHN divisions fall into the 'Have' category. They have the highest overall traffic (passenger+freight) through them, but they have good infrastructure and sound and unbiased controlling. You will find that they give reasonable slacks. They serve areas with lesser population densities, subsequentally number of halts is less. DNR is...
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getting upgraded bit by bit but it serves a area with very high population density leading to a huge number of halts thus it's gives ridiculous slacks to improve punctuality figures.
SEE/SPJ/DNR fall into category 2. They have higher passenger traffic, improving infrastructure and some poor tracks due to geographical constraints. They give massive slacks to cover up delays and number of halts is very high as population density is very high too.