Someone I have met through work turned me on to this. I found it very interesting, and kind of odd that I have never heard of this before???
Germany has reunited, much discussion here on babble and elsewhere of Korea unification China and Ireland, but never the subcontinent? Why is this?
There is also a name for it Akhand Bharat.
Here's some research reading for those interested
https://tribune.com.pk/story/1016612/pakistan-india-and-bangladesh-will-...
http://www.india.com/news/india/akhand-bharat-india-pakistan-utopian-uni...
https://www.huffingtonpost.in/markandey-katju/india-and-pakistan-must-re...
Now I did come across some links that are negative towards this but decided to take the position as a pro reunification poster for the time being.