I acknowledged Daisuke was the better skater (and I think his PCS should have been about 90 and Chan's around 88, in which case Chan still could have won)... but Daisuke had a UR 3F (which compared to a clean 3F with +GOE, meant he lost the value of a 2A... the double axel Chan missed), and only had one quad, and Takahashi had << on his SP combo.
In this instance, Nam went clean, without any errors and did a flawless 4+3 combo, 3A and 3Z. Hanyu had a great 3A, but the 4T was flawed (which should have gotten more -3's given it was both a UR and a stepout), and the 3Z+3T was off-axis (although I'd say the judges got the GOE correct on that one with mainly 0/-1 compared to +1s).
The main issue is the components scores... 45.31 would have been fine for a clean skate (Hanyu's PB is 46.61), but for one with an obvious error, there's no way it should have scored above 45. But you compare that to Nam getting 37.85, and it's like ... really, 7.5 points higher for a flawed skate?!
I agree that Nam had no reason to be upset with that skate (unless he felt he messed up a spin position or missed choreo or something), and the judges might have taken notice. Orser probably had a talking to him after that.