Only dog I have trained is my Chessie Bear, on a skinny day he's pushing 125. Would jump off a cliff for a duck, isn't phased by sitting in ice water, will beat 90% of dogs to a retrieve, but will eat your sandwich out of the blind. He's allowed to roam the property and yet stays next to the house to keep an eye on things(not fixed either). All the delivery people know him by name and hes never been in a fight with another dog. Great retriever, but as said above you can't force him to do anything he doesnt want to.