I am not making your point. If his class rules required oil at the lifters, and you bushed lifter bores, you could restrict flow to your discretion with the bushing and leave the stocking method of oiling off #1 main as is. Sanborn claims this fails #1 main.
Just as you spoke about those old cams with a groove on # 2&4 cam journals robbing the mains of oil. I had one of those cams. Failed my 2&4 mains after 40 runs.
You cannot feed other areas of the motor off of a main bearing because you get a pressure drop at that bearing. The stock oiling feeds all the drivers side lifters from number one main.
So the fix is to block the feed on the passenger side. Then re-supply the oil to number one in the opposite side and direction of feed with a crossover tube.
The stroker small block book method goes even further and does not allow any cam bearings that are fed by the mains, to feed the rockers, re-enforcing the supply to 2&4 mains as well.