lifter galley crossover tube

Yes I believe this is the post you are referring to B3.
I do not agree that the oil will always move to the low pressure area
And I do not agree that if the oil would move so fast that it cannot make the turn or there would be no oil pressure.
I posted earlier that my number 2&4 main bearings had lost bearing crush after 40 runs.
This engine had the Mopar tube kit in the block full grooved mains,
High volume/high pressure pump like my previous build before, with one exception. I put in an old comp cams cam that had full oiling grooves on journals, 2&4. Why did those two main bearing fail if it was the low pressure area? Engine had 75 pounds oil pressure easily.
I am reminded of an electrical question I once asked.
Why do transformers exist that have redo illusory high voltage. Eg. 600 volts. 2000 volts etc and the answer I was given is that voltage is the pressure. By the time we send the voltage through the wires to the next state or country. We hope to still have 240 volts when it gets to its destination or something to that effect.
We are taking our oil pressure readings at an area that is vary close to the output of the pump. That does not mean the pressure (remember the leakage) is the same at every point in the block.
What are the odds that those two cam journals just happen to coincide with the same two main bearings. Why did those bearings get hot. Why did the required volume of oil not get there.
Why can you not buy a new cam for an La engine that still has those grooves.

Just to add to my previous posts. In the book how to build big inch stroker small blocks by Jim sziligy? He introduces a mod I had never seen to oil the rockers directly from the main oil galley by drilling and tapping for a jumper tube. This is to convert to priority main oiling.
The #2&4 cam bearings are modified to completely cut off supplying oil to the rockers leaving all the oil to go to the main bearing with adequate volume. This is to prevent precisely the failure I just had.