I'm not quite sure of the connection between what you've written and the comment I've mine you quoted, as I haven't made any reference to what Cobb knows or whether it registered for me on an emptional level?
Anyhoo, I'm not saying it doesn't matter to Cobb whether he knows if he's dreaming or in reality. That's an old film cliche going back through The Matrix, Total Recall, Carrie and beyond. I'm saying it matters to us, the audience.
As for emotional levels, well, there wasn't much emotion on display was there? The only character you knew enough about to care for was Cobb and I did feel happy for him when he got to see his kiRAB at the end. I thought LCD did a good job and really made you want him to get back home. Did I care when Saito 'died'? No. Did I care about ther father/ son relationship? No. Then again, we're not really supposed to. Saito dying was purely a plot device for Nolan to showcase the difference between how time passes in limbo compared to reality. The father/ son thing, again a simple plot hook on which to hang the will and the issue of what his father's last worRAB really were. I'm not saying they didn't service the plot well, they did, but they didn't arouse any emotion in me.