Splitting in competitive gateways has long been a trick to save money, and in premium cabins the savings can be in the thousands. LAX and YVR are popular Pacific gateway choices with lower fares.

Contrary to the opinions in that thread, I really don't see how the practice is any more or less a violation of the CoC than back-to-back ticketing or any other abusive practice, but in reality no one is going to notice or care about occasional use and I do it anyway. Often it's across ticketing carriers which moots the question anyway, since often the deal from the gateway isn't a UA fare.