Back when Blissey was hot and DWB looked like a great option some people tried it out. It failed. The deck took a lot of set up and in the days of Magmortar you could just Flame Bluster away a Darkrai FTW. Now that Magmortar has faded I still find that the deck has trouble keeping up in the speedy T1-T3 Meta game. Most common examples : Kingdra Empoleon and AMU which can also snipe with Azelf X and blow to pieces that hard worked for Blissey with 4-9 energies on it with Mesprit X. So now... it still fails.
I know of one person who plays the deck , and I haven't seen it win or lose.
But DWB like people have said will be too slow , there is no way you can get a T2 blissey ,weavile and darkrai.