If the head, holding tank, hand pump are all below the waterline, can you omit a vented loop after the hand pump and before the overboard seacock?

This is from Don Caseys article on Boat US. I'm replumbing the head/holding tank on my boat this year to this configuration. I'm not worried about the lack of a vented loop as I close the discharge except during pump offshore. Plus it would be an easier and cleaner installation without the vented loop run high up the bulkhead as I have it now.

But what about an insurance survey (which I may have to have done this year as well)?

This leaves the extra connections and components of, pump, Y valve, holding tank vulnerable in the event of any leaks that could sink the boat if the seacock were left open.