This is nit-picky, so ignorable I guess, but I see peer assessment as useful when questions don't have answers that are easy to auto-grade.  There might for instance be a "definite" answer to a question about, say why a particular experiment is poorly designed that you're asking students to explain in a peer-assessed response, but the answer would be difficult to auto-grade.  Similarly, I've heard of a programming course that asks students to write code to draw a blue rectangle, which turns out to be difficult to auto-grade, but easy to peer-assess, and has a definite answer (yes, the response produced a blue rectangle).