Khan's current lectures are best thought of as placeholder material. A rough draft. Having a free, competent, standardized tutoring job available on every littl

Khan's current lectures are best thought of as placeholder material. A rough draft. Having a free, competent, standardized tutoring job available on every little subject is SO MUCH better than nothing at all that clearly the low-hanging fruit at this point is to just cover more parts of more subjects. Once you've got lots and lots of subjects covered, it would make sense to assess the field to figure out which lectures are working the least well and invest effort on improving those. Khan Academy is a system that lets us set a baseline and then incrementally improve from there. If this "deeper understanding" can be conveyed in lecture form, it seems inevitable that as the lectures improve, some of them will impart "deeper understanding". Or maybe they'll just add an extra "deeper understanding" course in addition to the current ones.