Actually, I remember seeing an "extra" mixture cable in a M.A.F C206 some months ago. The pilot said the cable; when pulled will allow fuel to flow freely from the tank direct to the injectors. Therefore bypassing fuel selectors, pumps, auxillary pumps etc.
Hmmmm....Gravity fed fuel injection on a C206....I'd like to see that..
Still doesn't resolve the problem of too much air in the tanks though, does it.
Only solution that comes to mind is better planning, which is usually a result of better training and more experience. Can't legislate dumbness out of the human equation.....of course, all this in relation to this event is presumptive of the pilot running the engines out of fuel - fuel starvation or fuel exhaustion - and there has been no word on the event from ATSB so perhaps we should not presume?