I would only let someone I know and trust work with my dogs - but that's because I'm paranoid.
I do think that for the average dog owner, this could definitely work. Often, the owner is the biggest obstacle that's preventing the dog from learning - they don't know what they're doing, they get frustrated, the dog learns nothing, the owners get more frustrated, etc. It's a cycle. However, if you remove the obstacle, the dog learns, the owners are happy, and everything's fine.
I think in a perfect world, every dog owner would be a great trainer, and everyone's dogs would be well-behaved. But it's not a perfect world, and I would much rather see people with well-behaved, well-trained dogs that were trained by somebody else, than see people with misbehaving, obnoxious dogs that they attempted to train themselves.
There are some people that are still good dog owners, but aren't good trainers - trainers have to learn HOW to teach, and there are many dogs that don't make good "first students". Like SpringerLover said, when you're learning to ride a horse, you don't start with a green horse, you start with a reliable, well-seasoned horse - the point is you learning to ride, not the horse learning how to be ridden. I think many people, when they're learning to train dogs, need to start with a dog that already has foundation work, in order to set the person up for success.
I do think that for the average dog owner, this could definitely work. Often, the owner is the biggest obstacle that's preventing the dog from learning - they don't know what they're doing, they get frustrated, the dog learns nothing, the owners get more frustrated, etc. It's a cycle. However, if you remove the obstacle, the dog learns, the owners are happy, and everything's fine.
I think in a perfect world, every dog owner would be a great trainer, and everyone's dogs would be well-behaved. But it's not a perfect world, and I would much rather see people with well-behaved, well-trained dogs that were trained by somebody else, than see people with misbehaving, obnoxious dogs that they attempted to train themselves.
There are some people that are still good dog owners, but aren't good trainers - trainers have to learn HOW to teach, and there are many dogs that don't make good "first students". Like SpringerLover said, when you're learning to ride a horse, you don't start with a green horse, you start with a reliable, well-seasoned horse - the point is you learning to ride, not the horse learning how to be ridden. I think many people, when they're learning to train dogs, need to start with a dog that already has foundation work, in order to set the person up for success.