Yes, it is good that they are increasing the efficiency of Rail transport In India.
Double-stack rail transport is a form of intermodal freight transport where railroad cars carry two layers of intermodal containers. Introduced in North America in 1984, double-stack has become increasingly common there, being used for nearly seventy percent of United States intermodal shipments. Using double-stack technology, a freight train of a given length can carry roughly twice as many containers, sharply reducing transport costs per container. On most North American railroads, special well cars are used for double-stack shipment to reduce the needed vertical clearance and to lower the center of gravity of a loaded car. In addition, the well car design reduces damage in transit and provides greater cargo security by cradling the lower containers so their doors cannot be opened. A succession of larger container sizes have been introduced to further increase shipping productivity on shipments within North America.
Australia: BHP Billiton used to run iron ore trains of 336 car length, 44,500 tonnes of iron ore, over 3 km long, six to eight locomotives including intermediate remote unit. This operation seems to have ceased since the trunk line was fully double tracked in May 2011.
Brazil: Carajás Railway 1,600 mm (5 ft 3 in) gauge iron ore typically 330-car trains, each 3 km long.
China: Daqin Railway coal trains—20,000 t, 3.2 km, 210 wagons.
en.wikipedia.org