How long do you sit on a dog?

I have a young dog that comes from good bloodlines. Got him when he was about 14 months old. But he had been put up in the kennel and never messed with the whole time before I got him, and was wild as a coyote and very ignorant. I put some handlin on him and he showed some progress for a while, then it was like he hit a brick wall and all progress quit and he even went backwards a bit. but I kept him around because the way I see it he has to spend some time in his second year learning what he should have learned in his first year. Physically he is a dog but mentally he is still a puppy. He's starting to be much more consistant now and I like the way he works. The last month i've hunted 4 times and he's hung with the big dogs, and he likes to hunt and I figgure he will start striking hogs once he figgures it out a little more. It would have been easy to get rid of him those first few months, being he was a grown dog and would stand right next to you with a scared coyote look on his face when the other dogs were baying 30 yards away. But really he is a 18 month old dog but has only lived and learned something besides how to eat and poop for about 4 months while I've had him.

Waylon