You can't forget something if you understood it. A concept is internalized when one understood the concept. Techniques to memorize something is not effective. Even worse techniques are glorified. Then one spends a lifetime polishing the techniques to memorize what they wanted to internalize in the first place. It's a trap.

Want to memorize something? Try to really understand what's going on. You cannot forget something if you already understood it. If you can't recall it, then maybe it's not that helpful to you or you didn't understand it in the first place at all.

The techniques to memorize something effectively are organic, an effect when someone tries to learn in their own way effectively. Starting with techniques is a trap.

How many people who have used Anki or whatever forms of memorization became world class at what they do? It's a distraction.