This isn't even the biggest concern really. The spies are worse.

Enemy has members in your group telling them what you're doing, where your strong teams are, and positioning their forces to win the key areas. 10, 8, 3 -- 8, 7, 5 -- 7, 6, 5, 3 -- whatever essentially.

The ninja war is less about tactics and more about espionage. Just like a real ninja war!!