Portland Police bored?

So last night, I get pulled over to SE Water Ave by a Portland Police Officer. He comes up, asks for insurance and DL, and asks why it SEEMED I went through the Grand Ave light fast. (I was traveling Westbound to SE Stark from having the best pizza in town at Flying Pie). He tells me it looks like I went through the light fast, the facts, we cleared the green light at 36 mph. The light was about to change as indicated by the flashing Don't Walk hand, however, I never saw the yellow light, even though he proceeded to inform me of the yellow light laws of Oregon. He was nice enough not issue a ticket, but we did wonder for what exactly? He had to proof of my speed since he was coming from Grand Ave, and the light was green?? Aaron is wondering if he had anything else better to do, it seemed like a waste of time. I am not too worried since i got nothing but a verbal warning, but I was just lost at what the REAL problem was....