Well, the first principle is not about spaced repetition but is more about active learning (wrong term?) vs. passive learning. In other words, don't memorize by playing it a bunch and hoping repetition will beget recall. Instead, play from memory as far as you can (in sections as described below), filling in and approximating whatever you can't remember exactly, but trying to recall parts in that section, even if you can't piece them together in sequence.
The second principle is the spaced repetition. That works for learning the muscle memory as well as the memorization, but let's just address memorization.
First I divide a piece into arbitrary sections, often pages but in information-dense music you've got to go a couple lines at a time. I do not usually divide at a sensible musical stopping point, because we remember the starts and ends of what we do much better than the middles. Choosing weird places to start and end helps get some of those middles into our heads; plus it's really easy to mentally track what you've done if it's at a page or line boundary.
Then, with sections A through, say, D, I'll go in roughly this order, with "A" meaning I play all notes in section A in the proper sequence, even if I have to wait a few seconds sometimes to recall what happens next.
A A A; B B B A A; C C C B B A; D D D C C B A; D D C B; D C; D
...adjusting sometimes to accommodate the different information densities of the different sections. After this you'll need some mental downtime because it sucks a lot out of you to recall so much. Later you can do sections E through H, etc.
By the time you've done that, you're halfway to your goal. You can then start increasing the tempo toward performance quality by responsible metronome practice. I like to do
(1) the above routine out of tempo, waiting as long as necessary before notes
(2) the above routine at any tempo with metronome, doesn't matter how ridiculously slow
(3) increasing the tempo gradually from there, not deviating from the "note-perfect" requirement