the stock setup has the rocker oiling restricted/timed. if your idea has a constant supply of oil going to the heads/rockers then the mains would not have more oil
The mains would have more oil because they would not be passing oil to the cam then to the rockers. The oil would stop at the cam bearing allowing the oil to stay at the crank. The hole feeding the rocker passage would be small so as not to flood the rockers and drop oil pressure. My thinking is to just feed the cam bearings crank and rods without starving them by pushing oil up to the rockers. Then feed the rockers separately.