Thank you. I suppose I was downvoted, hiding your careful response, because I appeared to be pitching a product. I was attempting a precise analogy, I had nothing to gain from the promotion. I was robbed on BART recently, and my judgment is off.

I've relied heavily on spaced practice for learning languages for travel. There are two phases to that experience: Study, where one takes in as much as possible, then real world practice without further study. I find myself wishing I'd memorized a play for the first phase, to access faster than a phrase book on the ground, with lots of pathway shortening while I travel. Learning models tend to assume learning is single-phased, though even more academic learning is two phased: acquire, then later apply.