When it comes to training methods, I say the rubber meets the road during deer season when we got fresh blood on the ground.
And yes, do train in the off season, but you will never make a training exercise as complicated as a wounded buck will during deer season and thus wounded deer will teach your dog, not you or me.
As far as breeds go, I am a Catahoula man but I don't think the breed is as important as the dogs willingness to hunt for you and be part of a team.
And so, like Beauty below who is a mixed Catahoula, and an all around family pet most of the year, when it is hunting season, she is in the woods helping put food on the table.
Too many people want a good tracking dog and don't understand that you need to let the dog to be a part of the family or the hunting club in the off season, and it will be there in the fall.
If you buy a tracking dog from me, I am always available for you to call and consult with if you need advise.