Hi David,
you wrote: ". But the closer you get to the source of the pressure, the higher the pressure still is, "
The pressure in a hydraulic system is going to be controlled by the leaks. The pressure will be the same through out the system, no matter where you check it as long as the fluid is not compressable.
I don't think the friction losses are significant enough in the oiling system of an engine to drop the pressure as much as the pressure in Geralds engine has dropped.
Jim R
