What was the purpose of Theon’s reaving along the Stony Shore?

Balon’s plan was that Theon’s reaving would provoke the North into deploying their forces away from the main thrust: “It may be that you will draw some of the northern lords out from behind their stone walls.”

Ironically, the only forces that responded were the Wild Rabbits, whereas when Theon diverged from the plan and had Dagmer attack Torrhen’s Square he actually did get the North to divert its military forces.