I've read the article (except skimming \ fast forwarding 3rd and 2nd paragraph from the end) and it wasn't there. No detailed info explaining why author's criticizing Khan Academy for not doing something it in my experience did.
Maybe you haven't read it?
I've read the article (except skimming \ fast forwarding 3rd and 2nd paragraph from the end) and it wasn't there. No detailed info explaining why author's criticizing Khan Academy for not doing something it in my experience did. Maybe you haven't read it?
This article is an example of a rather poor piece of writing. You can't blame people for skimming through it.