They probably wanted to prevent oil pressure loss if a right bank lifter popped out of the lifter bores, I would have used a much smaller line (1/8 to maybe 1/4 inch O.D.) to oil the driver side lifter oil galley to reduce the oil pressure loss if one of them came out
I've had blocks bush in all 16 lifter bores to do the same thing as well as fix any of them that were too big on the I.D. or made crooked