Going by past experiences, I am sure the double decker will be another prank, coutesy Indian Railways. I am pretty sure this trTin will not serve Goa. Just by having Madgaon as a terminating station will make no difference. Currently, the state of Goa is used as a corridor for ferrying passengers. Trans have 1 or 2 stops in Goa.
If this trains is actually meant to cater to the Goan travellor,let it halt at Thivim and Karmali. Let it run non-stop between Thivim and Panvel, only then will it serve its purpose