Let's say he was successful in driving Sansa and Arya apart. What was the next step of his master plan?
>>87019658
Convince the other lords to back sansa up, jon is a bastard and is too busy off with a foreign queen, the king of the norf should stay in the norf etc, then the lords pronounce sansa queen of the north, or just lady, then marry her. He then runs the entire north + vale with sansa and then use sansas hatred against cersei to march south against cersei to take the throne. It would have worked if it werent for OP bran ruining his shenanigans, and the white walkers I shuppose.