The pickup is probably uncovered pretty easily - they didn't understand windage, and the spray to the rod itself is as accurate as [censored] in a hurricane. The oil forms a rope that wraps around the crankshaft like taffy.
The oil supply to the rod (by pressure, scoop and dip, spray) is only refreshing the actual local pressure produced by crankshaft rotation, and is many times higher than nominal (gauge) pressure.
It's a function of RPM, bearing circumference (~ as journal diameter) and viscosity. If it "pumps dry" (refresh rate is slower than the leaks) the rod goes BANG.
Yes, a pressure system can uncover the pickup at speed as well - but there are fewer variables, and the remedies are well known (deep pan, baffles, windage tray).
