RPM and stock 360 pan
I'd rather use a Briggs & Stratton than a Pontiac lol.
I'm not sure 'failure to drain back' is entirely a lifter valley issue. Don't forget, much of what drains through those big passages falls right onto the crankshaft and (can) get whipped around so that it only eventually reaches the bottom of the sump. I think oil return is multi-faceted affair.
Either way, I've had big blocks lose their oil pressure from sucking the pan dry.....do nothing but let them sit a while and they start up with oil pressure again. These all had one thing in common - 100% stock oiling systems with HV pumps.
I also seem to recall reading/hearing about police cars with 440's that would starve for oil in high speed pursuits. These were considered properly maintained cars so I can't say they were low on oil, etc.
I'd be willing to bet if you took a bone stock 1970 Challenger 440-4 car and ran it on Bonneville, wide open, it'd run out of oil before it ran out of anything else.