Ok my opinion does not fall into this line.
Grow some patience. Work on keeping yourself and your dog calm and safe within the class. The chances of this dog EATING your dog here in class are pretty slim. If the dog is acting up, and you are near it, calmly walk your dog to the other side of the room.
Everyone's dog and every handler is at a different place. Working around other dogs might be what this dog needs to work on. Private lessons would not help at all.
If our trainer put all the reactive dogs in a class together, they would carry her out on a stretcher after the first class. Furthermore, reactive dogs really need to work around stable dogs.
And you and your dog need to stay calm and act appropriately in this setting around a dog that is not doing so hot. No where else will you be able to practice this safer. And the chances are, you will have plenty of opportunities outside of class where this experience will be invaluable.
It is great that in your opinion, you and your dog are ready for class #3.
Sometimes we are the stable, well behaved teams; sometimes we are the ones needing a little more patience.
I'll be damned if my trainer EVER requires me to put a prong collar on my dog. For one thing, they are not all that safe, they open and then what do you have, an unmanageable dog running around without a handle. Nothing wrong with the suggestion, but requiring that in my opinion is not appropriate. Requireing a collar the dog cannot slip, like a martingale or choke is ok for safety if the dog has slipped its collar.
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