The left turner had probably been yielding to oncoming traffic throughout the green, waiting in the intersection for a chance to turn left. This is pretty par for the course for such an intersection, and conscientious drivers stop on the yellow to allow the left turners a chance to go. Hustling to make the yellow, and thus forcing the left turner to complete the turn on a red, is an asshole move. Your "confused halt" was probably more of an epiphany of self-awareness brought on by doing something rude.
Gawd, another passive Portland driver. Next time chase down the mo-fo (right or wrong) and threaten him. DO feast on his organs, don't just talk about it! THAT, my friend, is textbook driving. You're welcome.
RTFM you sack of shit.