I have been active in dogs for over 15 years. I began showing Bearded Collies 35 yrs ago. I have finished several champions and have qualified for Westminister Kennel Club Show. I have also competed in obedience. I currently own 2 maltese, one long haired chihuahua mix and one terrier mix. One of my little maltese enjoys agility and my terrier mix is preparing to compete in obedience. My terrier mix suffers from separation anxiety and even though it is a slow process, I am happy to say that she is much improved.
I believe that each dog is an individual and there is no one-size-fits all training. There are basic approaches that are helpful, but the trainer needs to be mindful of each individual triggers and work with both dog and owner to solve these issues.