A couple of weeks ago I went and did Tombs with several pet barragers. I figured I'd bring a shout (Call of Protection), and see how that helped.
So, it seemed to help, or maybe we were just killing them quicker than they could attack the pets. But at one point, my pet was dead, and I needed to re-call the shout. Imagine my surprise when it didn't work. I couldn't activate it. Rez'd my pet, and was able to activate it again. I tried this several times over the run, with the same results. So, does this mean that my pet has to be alive to use it, or that it only affects my pet? The skill says "your animal companions" - so why does _my_ pet have to be alive to activate it?
Frustrated with this, the next go-round I figured I'd use a different skill - Otyugh's Cry. I was having all sorts of problems getting it to activate, and I figured out the problem just now when I re-read the description: "All animals in the area become hostile to your target and gain +20 armor for 30 seconds." Apparently I must've been trying to use it before battle, not during battle. Doh! Let this be a lesson to you. What lesson, I dunno.