This would allow Figxin's new army to gain sufficient combat experience, while also drawing out the new King's forces.
With the stalemate in the Northern Domain, the new King would surely come to suppress the "rebels" and aid his allies. It would be even better if he led the campaign in person.
Once both forces were gathered in the Northern Domain, he could wipe them out in one fell swoop. This would also serve as a demonstration to the other Lords of Sutton. The intelligent ones would understand that they shouldn't get in the way of Figxin's march to the throne.
As for why Zog was so confident he could take on both Duke Welton's army and Sutton's potential reinforcements simultaneously...
...it could only be said that the Deep Research Institute still had plenty of tricks up its sleeve.
Now, only one question remained: whether or not to share this intelligence with Figxin.
