Originally Posted by weero
There is one major exception, this being RTW travel. In this case only the travel between stopover points counts as itinerary.
So if you fly from Australia to Hawaii with NZ (via AKL), you can bring 2x70 ln as a general member if you do not stop in AKL. If you do so, then you will be capped at 20 kg.
Some checkin agents do not know this and these are the lovely times when you have to insit on a supervisor as they are never ever willing to look it up.
*A RTW travel specifically applies the "piece concept" to the entire journey, i.e. 2x or 3x 70 lb/32 kg bags.
I believe it is standard practice to extend the piece concept to cover all itineraries ticketed in conjunction with origin, destination, stopover, or connection point in North America.
For instance, NZ advertises in London that since their LHR-AKL flight stops in LAX, the 2x 32 kg allowance applies (they actually advertise "take up to 64kg") rather than the much stingier allowance that would apply when you go from LHR-AKL via Asia on another carrier. In this case, the ticket doesn't even reflect a US point as it is a through flight number (NZ1 or 2). But the US/North America rules still apply.
I believe part of the theory is that if you have an itinerary ticketed you should be able to carry the same bags throughout and not have rules be more or less generous on different segments. The piece concept outranks the weight concept so piece concept applies where there is a conflict.
Charles