The full title of this book is When Pigs Fly! Training Success with Impossible Dogs!
Elka is not an impossible dog. She's very smart and sometimes difficult and frustrating because of her intelligence (a combination of "What'll you give me for it?" and "I don't see the point", I'm sure.)
When Pigs Fly! uses clicker, treats, and basic notion of drives and motivations to make working with your dog the joy you hoped it would be.
Both the title and the bull terrier taking the agility jump are what drew me to this book. Improbably, I think Bull Terriers are appealing and adorable looking dogs. They are not, in general, considered to be "operant" dogs, to use the book's terminology. An operant dog is checking out what you're doing and what you're expecting, and offers behaviors to get reinforced and rewarded. If you've been unable to pinpoint and build drive in your dog, by contrast, she could care less that you've turned her loose in a fenced area, and would much rather check out what's over there, and if there's a toy, etc.
In the course of When Pigs Fly!, you figure out what your dog likes as rewards (getting to jump on you, getting to run around, getting that toy) as opposed to necessarily relying on a handful of hot dogs. The hot dogs (or treat of your choice) comem into it, but you've got to get your dog revved up and paying attention to you and trying to anticipate if you're going to go nuts for fun or what. As I've said, Bull Terriers are not known for their licks in the Obedience World, but Killion has (at least) three Obedience titled Bull Terriers.
The book also does basic and useful troubleshooting towards the back, using an "ABC" setup. A for Antecedent, is what causes B, for Behavior, which is what gets C the Consequence. So, to drastically summarize, it's up to you as the owner to figure out the A that causes the Behavior you don't like so that the Consequence is something that matters to your dog. If you know what makes your dog bark, for instance, you can anticipate it (another A!), replace the "bark" (another B!) with something like "go lay down" or "go to the door and wait" or "poke me with your nose because there's somebody at the door", and the Consequence will be 1. rewards for the dog for behaving appropriate and calmly and 2. rewards for you and your visitors, because you figured out the problem and now your dog isn't a spaz barker.
If I've laid this out unclearly, I apologize. But it really is quite the good book. I read and enjoyed it once, before I picked up a clicker with Elka, and now that I've made that step in training, I felt that I got much more out of it. Elka does too, I'm sure.