Low oil pressure?

O.K. I think you guys are thinking it all wrong,
1) You have a oil pump pumping oil, it will not make pressure till it hits a dead end, and that is the bearings. If you change your oil and filter and start the engine there is no pressure till the filter fills up the oil is pushed through the engine and hits the bearings, now it has pressure.
2) You are talking about the filter draining back, oil looping in and out of the filter and this is impossible without a hole back to the pan, the pump wont stop pumping oil even if there is no pressure and it will fill the engine galleys and it will hit the bearings at the end of the line. Then and only then will it drain back in the pan to get picked up again.