Its genuinely a good idea...I was thinking if Pakistan is smart enough, they could have done in long time back which is more potent than waging an futile insurgency war...But the catch of the situation is that, in exiting Pakistan admistered kashmir, many Non Kashmir people got settled. How do you ensure that Non Kashmir did not vote in the election...And the most important part is that you have to get back the Kashmir from China and China to return Aksai Chin that is occupied from India on its east.
So as long as certain pre conditions are met, it will not carry any value for India...But if Pakistan somehow manage to carry out with all these situation satisfied, it will be a diplomatic coup for them...