I finally watched your video, Steve. The oil pressure does really drop off suddenly in some of the right handers, but it appears that when you are over 4,200 rpms or so, it doesn't do it nearly as much. In some left handers it also drops when you were at really low revs, like around 2,000.
Pressure is mostly dependent on rpms, so I think that is most of what is going on. I thought that the Boxster oiling problems were supposed to happen in left handers, though, not rights?
Over the course of a session, the oil pressure can drop form the oil getting hot, but there shouldn't be a large drop in pressure, maybe 5 lbs or so.
I used to race a first generation RX7, and had the oil pressure gauge mounted high in the dash, right in my line of sight, so it was easy to keep an eye on it. The pressure on that car really did vary a great deal depending on the rpms; from about 35 lbs at 3,000 to 85 lbs at 7,500, and it took a bit of getting used to after I mounted the pressure gauge where I could see it. My experience on a warm-up or cool-off lap was what you are seeing, lots of changes in the pressure, but on a hot lap where the rpms were up all the time, the pressure didn't really fluctuate much.
Oh, and try to keep your hands properly positioned on the wheel - it just
looks so much cooler when they are at 3 and 9 o'clock!