If it's designed anything like the cartridge setup is in my Kia 3.8L, yes, that's how it works. I always noticed the same thing, and that after sitting for awhile, the oil pressure light took a few seconds to turn off. Dealer told me this was normal, and even tested it on other vehicles with the same motor. Timing chain is a bit noisy until pressure builds, but that's normal considering that the timing chain tensioner is fed by oil pressure.
Why they did it this way, I have no idea. But the motor still purrs with nearly 100k miles.