With a full groove bearing you feed some oil all the time out to the rods.
There are reasons why getting some oil to the rods full time but saying then causes a massive **** show.
What I will say is if you want to know the why just compare the liking system of the small block Chrysler with the small block Chevy.
The differences you see are the reasons.
Anything you can do to stop taking oil from the main bearings to oil the valve gear is a good thing.
Of course if you shift at 5500 none of this stuff applies.