Kerbal Space Program

A little background: I was flying a spaceplane with a fuel configuration that looked something like the following and noticed that when I switched the RAPIER engines to closed-cycle, the center engine was running out of oxidizer before the side engines.

After a bit of testing, I have determined the following:
- Engines drawing fuel from jet fuel tanks can draw oxidizer from unconnected tanks. (see attached Oxidizer Testbed I craft file)
- The illegal tanks must be an ancestor of the jet fuel tank in the craft's part tree or in the same stack as an ancestor. (see Oxidizer Testbed II and III)
- Drawing fuel from a liquid fuel+oxidizer tank that contains fuel but no oxidizer does not cause this bug. (see Oxidizer Testbed IV)
- This will occur even after the jet fuel tank runs out of fuel. (see Oxidizer Testbed V)
- The oxidizer will be pulled from the (hierarchically?) furthest tank that meets the above conditions. (see Oxidizer Testbed V and note while the engines are firing that the oxidizer in the smaller and larger tanks of the center stack will deplete simultaneously)

Some additional notes:
- This will occur even without the modular girder segments. Those are present just to make it clear how the tanks are connected.
- The Mk2 Liquid Fuel Fuselage and Mk2 Liquid Fuel Fuselage Short parts exhibit the same behavior as the Mk1 Fuselage - Jet Fuel shown.