Not yet, no. I intentionally kept all my heavy cavalry in the rear to intercept routers last night but they didn't stop them. In fact, after about 10000 runaways had passed through them , they themselves turned and ran without having a sniff of combat

I guess their morale took a heavy denting from seeing all the disorder, though strangely, I gained an highly rated tactical,lower rated strategic victory overall(LOPs intact).
Maybe it doesn't work in the demo?