My strip canoes get dynel wear strips when new. No reason to wait until they wear to the wood core. I put a lot of hard miles on my canoes and I've had single days that would easily or i shoukd say, have worn through multiple layers of e glass. On my most used canoe I have replaced the dynel wear strips on the bow twice and it needs it again. No real reason to wait on any boat. If I were to buy a new tripping canoe, which isn't likely, I would put the wear strips on before the first significant trip.
Mark