Treats are like any other tool used for training. Not every training tool works on every dog. We have to figure out what method works best for each dog that comes in to training.
Some dogs are hyper, excited, up beat, just full of energy. Typically we do not like to use treats or food for this type of dog. Reason being is because the drive to work is already in place. It's a matter of finding what will calm him down so he will be more focused. Introducing food can cause the dog to be even more up-beat or hyper.
We like to introduce treats as a training tool to laid back, lazy dogs who just need a little boost to get their attention. We will even use treats for aggressive dogs, especially human aggressive dogs. This is because we can gain their trust with treats.
Treats can be a good training tool or a bad training tool when it comes to teaching your dog. Always pay attention to how your dog responds when using treats. If he is over excited while using them, it can cause chaos and you will not get anywhere. If he is on cue an you have his un-divided attention, you are doing everything right.
Side note: do not over feed your dog. If you use treats or food, take that portion out of your dogs regular feeding to illuminate over feeding.