WAM 4 - Father of the Nation for RailFans - Vikas Kumar

Loco abhi flop nahi hua hai. It's development was stalled because of of it's high axle load that was giving problems on Indian tracks. The loco is heavier than the present EMD's ( DP4,DG4 series) as it has a higher powered engine ( which adds a lot of weight) and it is in general heavier to provide more starting tractive effort and haul heavier loads at higher balancing speeds. In addition, it has more crash-worthy features and toilets, A/C for the running crew. All that cannot be accommodated in a short locomotive and will need a longer locomotive. DLW and RDSO had designed indigenous bogies to support the locomotives requirements. There is very less scope for making the loco shorter with the same specs and making it longer than it is now, will make it practically useless.
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Another reason for the lack of dual cabs, is that these locos, along with the original EMD's were designed to be used in MU configuration only. You can see pics of EMD's on American railroads. All the high HP locos are mostly single cab designs and are always used in MU with the two cabins facing outwards. They were never designed to be operated in LHF. IR did a lot of jugaad to enable LHF mode operations in EMDs, as we were accustomed to operating the ALCOs in LHF.
DLW is quite good at it's job and has done a tremendous amount of innovation so far ( The WDM3D series being the top of them). Locos are developed from scratch very rarely. Most railways around the world, be it ours or the more 'advanced' other countries only pick existing designs and modify them according to their needs, adding a bit of their own innovation. DLW does the same thing and is quite good at it.
Thankfully, this loco's development is finally back on track. Hopefully, we will soon see WDG5 multiple units cruising on the freight corridors!