Jaro is 16 months and still wants to chew.A lot. He has raw bones and antlers but I wanted to get something a bit softer. He destroys all stuffies even the Tuffy ones. I have not given him a Nylabone since he was tiny, a bit afraid of them. So today I bought him one, the big one with the fist end for aggressive chewers. In an hour or so he has put some considerable chew marks in the big end. Is this normal? When do you know it is time to throw them out? Should I clip off any little pointy ends after he chews?