Winter 18-19
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* perfect timing - ended 1-2 minutes early with break and questions
* could add a little more on optimization - techniques, mindset, examples, live optimizations?
* hammer home more difference between when to use headers vs. when to use linked list (e.g. why not linked list for coalescing?)

Spring 18-19
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* short video - just on optimization
* more interactivity with optimization - e.g. use C. Gregg's "let's optimize this" exercise?
* more on caching?