Forget about throwing NW towards BD, because in today's age no country will ever use it again after the world has seen the outcome of atomic falls in Hiroshima and Nagasaki in 1945. NW is only a deterrent. Thing is, BD military will not send troops along India-Pak border and the political people do not have the stomach to do such a silly thing. India Pakistan war is simply not a BD proxy war.
However, in case of a warlike situation, the best for Pakistan would be for BD to assemble its troops along the BD-India border. Even if BD does not act and just stay put, even then it will cause IA to divide its troops to both western and eastern fronts because IA just would not know the true intention of BD military. As a result, India will be almost unable to spread its war in the western front from Kashmir in the north to Run of Kacch in the south, a 1000 km stretch.
I only hope, such an understanding between BD and Pakistan will be established that will result in a stalemate in the India Pakistan war front. If Pakistan is completely defeated, there is little prospect BD would be able to protect its sovereignty from the Indian onslaught. I think, a strong Pakistan deters India from shallowing BD, and a little stronger BD will also cause similar effect in India's western front.