Indeed, which is generally why when I'm active the enemy try to move into every region I can reach. This is also where the two turn move problem comes into play, cause they can see me in the new region on the same turn as I am arriving. Course they have to have someone close by to make use of it, but it has certainly happened before. When your realm is constantly besieged by 4-5 Arcaean infiltrators you tend to start looking at ways to limit them.
If the enemy has to task three or four active knights with nothing but hunting you down, I would say you are more than pulling your fair weight for your realm.
It's all about player skill. If you know what you're doing, you can seriously hamper an enemy realm. If you don't know what you're doing, the most damage you can do is making the enemy Judge burn some honor/prestige points.
