Ian
What current turbine engine uses a 'total loss' oil system? Because the ones I'm familiar with are quite the opposite, with extremely low oil consumption rates when healthy (and any lube system can loose oil when it's damaged).
Turbine engines typically consume far more oil when operating at low power/idle - the lube systems use pressure differentials to keep the oil where it's supposed to be and that doesn't work as well with low power and low pressure differentials. That means that an aircraft taxing around an airport typically consumes more oil than it will during cruise.
If anyone was really interested in the subject, the absolute first thing they'd do is start sampling the air around large airports - lots of aircraft operating engines at low power and consuming lots of oil.
That so far no one has tells me everything I need to know.