hard or soft copper line for a valley oil gallery bypass line?

Jadaharabi said
So putting a 5/16(cross over) hole in the side of a 1/2in passenger side oil galley, will not slow down the oil after the 5/16 hole? I believe it will.

I have to agree. And how much oil pressure is at #1 main that is trying to feed a cam bearing and 8 lifters with a 9/32 oil passage.