I think that most of you have hit upon the theme of the lesson. I will include more on the convenience factor when I revise.
As many have said, scheduling "academic life" into "real life" is an important consideration (although I always question that wording in that academic life is not "unreal." :) ).
The motivating factor of "just-in-time" learning and being "ready" when students want/need/desire to learn is key.