Just ran across a reference to this cryptically named addon today: Another Retreat
It sets the new interval after a lapse to whatever the interval was before the one that led to a lapse. This is a nice way of solving the problem of finding a decent post-lapse interval.
Be default, Anki uses an interval of one day; effectively starting over from square one just because you couldn’t remember that card after not seeing it for 3 months (even though the answer was on the tip of your tongue). Yes, I’ve written about this default behavior before; it’s inefficient and a waste of time; complete overkill.
I wrote an addon that uses Anki’s native capability to set the post-lapse interval to a percentage of the previous one. My addon attempts to shoot for an 85% success rate (on average) on that post-lapse interval because I think that success rate is the sweet-spot between too easy and too hard. Anyway, it works, but the way Another Retreat works is perhaps simpler; a technique I’ve considered before, but never felt motivated to code myself.
Anyway, I think both my addon and Another Retreat probably behave very similarly. I may try it out some day or maybe not.