The one thing to consider, however, is that link not tracked. Specifically, it's a problem if you either already know the material or you don't care about specific prompts. The problem is simple to overcome if you can maintain the deck of prompts. The problem is harder to address for sites that integrate spaced repetition prompts directly into them, like blog post - quantum country, which presume to know exactly which prompts you need to answer, when, and don't give the user much control over the experience.