Good point apple.
But at the same time, trainers all got training somewhere, either themselves or others. While it has worked wonders for my life with and away from my dogs, no one approach is best for all.
I do see a lot of fatalism in this thread. In one post I say my terrier is the "real killer". But now I know it's not him, it's me sending signals. Turns out he is more focused than the lab/pit, who still likes to challenge me.
If you start by telling yourself a story about what the dig will do, it will certainly come to pass.