Now that the topic has been brought up, one thing that I would love to hear an explanation for is why for example, LAX/SFO-SYD flights don't simply *always* have a stop in HNL. (I guess like the JFK-JNB flights regularly have to stop in Dakar)

There is no great time pressure for the flights to arrive in SYD at the time they do -- both these planes spend quite a number of hours on the ground anyway. Passengers flying these flights are not exactly in a rush to get where they're going, by an extra hour. Going halfway around the world, passengers are a little more forgiving.

The advantage to doing so, which is why I ask, is that stopping in HNL could cut the needed fuel load significantly. By breaking the journey into two legs, and not having to load all the fuel at the beginning, you save flying tons of fuel around.

Others have pointed out that the cost/gain of landing in HNL outweighs it, and then you need to plan for crew time limits, etc. But it seems feasible given these recent examples.

I'd really like to know what factors come into play, maybe if only a UA route planner visited these boards and could comment...