Unfortunately there are still some trainers out there who haven't updated their skills, and they prefer to "dominate" and use different types of "mild" punishment on dogs during training. This includes everything from using prong, choke chain, citronella, and shock collars, to ear pinching, using loud noises like shake cans, squirting the dog with water, and yelling at them. Basically the trainer is teaching the dog what behavior ISN'T wanted by punishing the dog. (I've seen my fill of that at dog shows, where a few of the handlers pinch the dog's ear to make him/her behave in the ring. :x )
But many trainers have adopted the newer positive, rewards based methods of training. Using this method is more effective because you're showing your dog what behaviors you want by rewarding. Your dog actually makes his/her own choice of how to behave and learns in a fun, loving environment. Clicker training falls into this category. Read Ian Dunbar books to learn more. When looking for a trainer, find someone who is a certified pet dog trainer CPDT, that means they belong to the APDT organization.
Many of the Cavalier books state that because Cavaliers are a 'soft' breed they need to be trained with gentleness, and this is true. Really, all breeds of dogs deserve to be trained with love, respect and dignity.