The entire second oil galley (drivers side) is filled exclusively from number 1 main. That galley also feeds 8 lifters
The entire drivers side galley that feeds 8 more lifter bores from number 1 main is missing from the drawing. The passenger side galley is not sealed on the passenger side. It still feeds the other side of the engine and 8 more lifters. How is his drawing representative of that. It's not.
Sanborn claimed to repeatedly fail number one main until he blocked the supply to the other side. That main fails from a lack of restriction. That is also what creates the velocity issue at number 4. The oil is always rushing down the freeway trying To fill 16 leaks and another entires galley and starves the first one or two.
His drawing does not show that. Imho