Seeing All Discussion Posts Authored by a Student in D2L version 10.3
In trying to make the discussion view more compact, D2L 10.3 sacrifices the ease of seeing all posts authored by a student in one handy place. Here is one workaround that is not terribly onerous.
This document describes one way to see all posts authored by a student in D2L 10.3.
Start by - counter-intuitively - going to Classlist in the navbar.
Then select "view progress" from the dropdown menu next to the student you are interested in assessing.
Finally, choose "Discussions" from the menu at the left. This will bring up links to of all threads authored by the student.