A few months ago I had the following visits/transits in the space of a couple of weeks
AKL-LAX-AKL <12 hours in USA
AKL-LAX-SFO-SYD <12 hours in USA
LHR-LAX-SYD ~3 hours in USA
AKL-HNL-LAX-SYD ~1 day in USA
SYD-LAX-SYD <16 hours in USA
No problems at immigration at all