Spencer is really the nuts-and-bolts for setting up training tests (mostly for HT setups).
For me, the best thing is to have a VERY critical eye standing right there behind the line coaching. Second best is to have them throwing for me, the come roaring up on the wheeler and say "What the H#!! did you do THAT for?"
Works for me every time.
Peake, you have mentioned wanting to run that ghost-colored dog in a Derby or two. Your best weapon in that endeavor is to find some like-minded individuals to train with who can help you be successful. You can't know what to train on for Derby from a book. By the time ANY book gets through the publishing process, it will be out of date where Derby is concerned. Yes, it evolves that quickly.