That's just typical veiled chameleon behavior. As for how hard they bite, my first one drew blood one time when he bit my finger. You can't pull away when they latch on, for fear of hurting them, but luckily it's a quick release. As I just said in another thread, my current 10 month old...
Ha, ha, me too. Wyatt is alias Pissy Lizard; see my avatar. He came in hissing as a tiny 2 month old, and has down graded from biting to head-butting. He's now 10 months old, and I just laugh at his antics. I love him the way he is. For warm fuzzies I have a cat.
Just an observation from one without a lot of experience with chameleons. I think most of the people on this forum are trying to duplicate, in a microcosm, what they perceive a wild chameleon's experience to be. In other words, in the wild, it wouldn't be the norm to find a tree full of most...