and you really manage to paint a picture of a damaging past with a few brief lines

Actually, Jensen's whole characterization makes it pretty obvious he's had a damaging past, I think I meant the few lines you do write here and there to give an idea about that past really paint a vivid picture of how damaging it must have been.
The line I'm refering to in this part is:
but a dog’s never asked if he was retarded before, or cared if he froze and couldn’t think of what to say

Am I making sense? Sometimes it's rather hard for me to express myself.