Are you familiar with Bas? He is a world renown fruit tree expert now located in Australia- he worked as a consultant for some of the largest Washington state producers in the '90’s. Good Fruit Grower has often run articles written by him. There’s an Australian industry mag that run a lot more of his articles and markets his pruning books. As I said, I believe he’s the one who wrote a Pomona article 20 years ago espousing using notching for this purpose.
He writes a lot about spur renewal pruning- especially in pears. Cycles shoots in and out on a 3-year program.