I'll third the vote for James Lamb Free. Never found anything in that "other writer's" books that was Revolutionary. Oop's don't want to start trouble.
In my observations, a 75 lb field trials dog is lean and if a different hunter had it that was feeding/working the lab a different way, that same lab would be nearly 100 lbs.
Just like, I am sitting here at 220 lbs [:'(], but if I were in shape for a marathon, I'd be about 165 lbs.