[mmt]

Interestingly, the efficiency ratio you suggest appears to be reflected in the ratio between the overall cost (including ground transportation at the other end) of flying SFBA-SoCal and driving.

Whenever I've spot-checked, the break-even is at 2 people, which tends to make flying more attractive for time/fatigue reasons (only barely, at some points in history) even for 2, and sometimes worth the cost premium for 3. For a family of 4 or more, even with the increased fuel cost (but generally not other operating costs) of something like a minivan, driving saves too much money to pass up.

[mehrdadn]

That's interesting, thanks for mentioning this!