Great to hear you have such an intelligent dog. Sure do wish my bird dog would learn his lesson, I've had to pull quills on 4 separate occasions. Not a fun job for me or him, but it won't stop him from going after the next.
Do you have fisher in NY? We are lucky enough to have a decent population. Absolutely unbelievable animal to watch going through the woods, and a natural porcupine predator. They have no fear that I've seen.
