I find Wardogs usefull against enemy light (without armor) archers, they cause confusion and all the archers set to skirmish will run, die and just get out of the fight scene which is the best afterall, beacause if they are running they arent firing.

In overall i like Wardogs on the enemy side, because my troops like the damm poodles with a little potato and salad on the side...its usally a pretty soft and tasty meal....