If you've been reading the latest posts, you're now pretty well primed in microlearning, from what it is to where it fits in the learning lifecycle.
Because microlearning is a "hot" trend, there is some wiggle room around its design, implementation, and use. Yes, some aspects are constant (i.e., it reinforces specific skills), and some are, well... interpretive, like how many minutes constitute "short" bits of time.
Scaffolding (sequenced, leveled instruction that leads learners to mastery) falls into that last category. Ask a few digital learning specialists about where it rests in microlearning, and guess what? Yep, many will have different points of view, a few of which I will share here.