Again, I think Denzel's smile at the top sets the whole tone for his scene, and a big part of that has less to do with the writing or his characterization of that, but rather that it's the Denzel smile, we've become used to - http://media.salon.com/2011/04/slideshow_good_guys_gone_bad-slide-6.jpg
It's the bad guy you like look. Which allows you to laugh with him. But is that really called for in the writing? Again though it's coming rom my perceptions of seeing JEJ where it really was fear that was being conveyed to help sympathize with the son, while really wanting to understand where the father's coming from. In Denzel's it's like you're supposed to already understand and agree with where he's coming from. Which is why so many lines seem to get lost.