Separate design changes and design changes due to amendment Be sure to cover alternatives Collision system is too coupled Example of game simulation algorithm ie, ball hitting two things Emphasize that recomputation of collisions is O(n) It's complex, so emphasize why it's a good idea Diagram inbetween overview layer diagram and MDD (just really important classes) Possibly split out individual parts of MDD and put them with sections Object models How triggers are stored and triggered What's in AbstractTrigger What happens when it's triggered Including what goes on within the gizmos Representation choices ie, heap (or whatever) for event simulator Test inputs (coverage) ie, a script for each action in the user manual, and for error actions Integration tests Drawbacks of testing strategies Usability tests Next time primary grading: design changes and evaluation