Effectiveness of a spaced repetition system (SRS) for memorizing tactical patterns for long-term skill gain? After reading Micheal de Maza's article 400 Points in 400 Days and the paper Training in Chess: A Scientific Approach by Gobet and Jansen, 
I have come to the conclusion that effective gains in chess skill for players below the A-class rating (&lt;1900) must come from an equal gain in tactical ability. This is pretty well known in the chess community, and most people, when asked how to improve, will point to tactics.

Once we accept this idea of tactics being the foundation of amateur (&lt;1900) improvement, it becomes a simple matter of methods, results and efficiency. In this regard, most chess players will look to books and websites which offer "chess puzzles". Some of the more popular websites, CTS (Chess Tactics Server) and ChessTempo, offer random puzzles, ordered by difficulty. Having used these websites for the better part of two years, one of the main problems I've found is the loss of "sharpness" or "board vision" when the regularity of puzzle reviews are interrupted. Often, even a gap of 1 week can severely cripple any progress made in tactical ability, so that constant daily practice is needed to maintain any growth. 

Then I read about Micheal de Maza (from an article by Dan Heisman) and his method to increase 400+ rating points in a little more than a year. The crux of his method is what he calls "the seven circles" where he does 7 passes through a chess puzzle book, at which point he can solve the puzzles near instantly. In other words, he has memorized the puzzles and their solutions by sight. 

Now it is my opinion that the book he chose to "memorize" (Chess Manual of Combinations) had a greater contribution than his actual method (the method is very inefficient, as I will discuss later) but I also believe that the memorization component was essential to sustained (i.e permanent) chess growth. Looking through the Chess Manual of Combinations, I can see that it follows many of the principles laid out in the second paper (especially regarding the building up of positions from the simple to the complex to create an internal hierarchy); it is also ordered by theme and difficulty. 

But the question remains, what is the most efficient way to memorize this material? Certainly, doing seven passes through the book seems to be the most inefficient way (brute force usually is).

I am a big fan of spaced repetition software such as Anki, and I think that this software can be combined with the memorization method to yield some significant results, but before I begin such an undertaking I wanted to ask if anyone has already tried a similar approach (if not spaced repetition, at least the memorization of puzzles) and what results they obtained (particularly if it was quantitative, i.e changes in ratings). 

Also, I have "Anki-ed" the Manual of Chess Combinations (Volume 1a only, 2a is in the works) and am wondering if anyone else is willing to experiment with this method along with me.
It is just anecdotal, and correlation is not the same as causation, but a few years ago I started using the Mnemosyne spaced repetition program to memorize


Opening lines (a few thousand cards here alone)
Positions from

Yusupov, Build Up Your Chess et al
Hellsten, Mastering Chess Strategy
Ivashchenko, Manual of Chess Combinations
Rosen, Chess Endgame Training
My own games where I had made a bad decision



During this time, my USCF rating, which had never moved much as an adult, went from under 1800 to over 2000.