I've taken advantage of the MPM rules for Australia to Europe via the US. My wife and I bought the following itinerary to break and rejoin our RTW last year.
MEL-HNL
OGG-DFW-AUS
AUS-DFW-LGW-NCE
NCE-ZRH-DFW-AUS
AUS-LAX-AKL
CHC-SYD
The AA fare was MEL-NCE-SYD with 2 stopovers allowed each way, this ended up being quite a lot cheaper than MEL-Austin alone! We could have done LON-HEL-LON as well for the same fare and 20 extra SC's. (Plus a bit more out of the US segments, could have done AUS-DFW-LAX-AKL, etc)