I actually book this about 2 times a year SYD-LAX/SFO-LHR. The flight is really not that longer to go via the USA and you get a US stop over via an asian one. Most of the fares actually allow 3-4 stopovers if I remember correctly -- so you can end up with a few US visits and then the trip over the atlantic.

The killer routing for me is SYD-IAD-EZE .. so 15 + 6 + 10 ... that one does me in! Did that back to back on the return after a friend's wedding in Buenos Aires and I don't think I will be repeating!

On top of UA -- V Australia pushes this pretty hard via their alliance with Virgin atlantic.