It's been a few years since I had my materials/heat transfer/mechanical design courses, but temperature is most certainly a factor in fatigue and is a variable in fatigue equations. That's about all I can say without whipping out a book or burning my brain's clutch up trying to remember those equations though...
Either way, things are a lot different now than they were 40-50 years ago. Spring pressures in the 60's were 80-90 seat with 200-250 open. Now we run 50-100 lbs over that even on mild flat tappet applications. We also don't use umbrella seals anymore, we have positive stop seals, Viton seals, etc. that do a lot better job controlling the oil.
On higher rpm applications, it's very common to see valve cover spray bars, and in Cup applications, it's common to see both the cam tunnel/lifter valley as well as the area under the valve covers flooded with oil. Now obviously, none of us here are talking about circle track or Cup motors, but I would hesitate to say that oil up top is a bad thing unless you can't keep oil in the bottom....
However, my point is that I'm often reluctant to do things "the way Ford designed it in the 60's" just because the engines that we build these days don't resemble the engines from the 60's.
FWIW, I've never used a drip rail.....or a valley pan.....or an oil slinger.
However, I do work the drains in the heads, and in some cases, I will use some kind of restrictor. Most of my engines now are oiled through the pushrods though, and the lifters meter the oil quite well in most cases. I also use the Milodon/Moroso pans that are 7-8 quart capacity.
Another revelation that I'm migrating towards is that in most cases, a high volume/high pressure oil pump just isn't necessary. I would base it on bearing clearances and the engine's purpose. I can show you some bearings that came back from a season's worth of drag racing, with 55 psi on the gauge...I would have reused them. Most guys want to see 70-80 psi on the gauge when they're in the gas, but pushing large volumes of oil at high pressures will rob horsepower.
As Jay pointed out, a high volume pump (especially without restrictions) will pull large amounts of oil out of the pan. If you're going to use a factory style pan with a HV pump, I would restrict, and run the windage tray with an extra quart of oil in the pan.
Drip rails will also play with the rocker arm geometry, so do your pushrod measuring with the setup you're going to run.
