Four years later

Dear reader,
It has been years since the last post and still I get emails and comments about this topic which is of interest to highly self-motivated learners around the world. Consequently, here is a post to let you know how I have progressed with SuperMemo and procedural learning over this time. I provide several links back to old posts, as much for my benefit as yours, because it's important to stitch it together with the rest of what I've written.

Props

1. I have continued to learn the following procedural items through SuperMemo: keyboard shortcuts, programming, mathematics (mainly engineering and financial), chemistry.
2. I have not continued using SuperMemo to learn Rubik's cube, guitar or violin, although I have continued to practise each of these outside of SM.

The primary difference between these two categories is that the first is not very prop-dependent; at most I need pen, paper and calculator. Although I noticed this problem way back when I wrote How to set up a procedural collection, I didn't realise how much of an effect the props would have.

Keyboard shortcuts
As described here, I believe the trick to keyboard shortcuts is answering the item by touching the keys. Consequently, when the question is asked on SM, it shows the black keyboard. When I click Show Answer, it shows the coloured dots and the answer box. This has continued to work nicely.

Programming

By the same token, many programming items in my collection are of the type shown below.  

Whichever language you are using, syntax is a type of basic knowledge that you'll need. However, watch out for interference if you're learning multiple similar languages. As Piotr Wozniak says in 20 rules, "Interference is probably the single greatest cause of forgetting in collections of an experienced user of SuperMemo". Some solutions that I have applied are: 1) master one language above all others (like a first language), 2) by all means add items from other languages, but if there's interference with your 'first' language, delete the secondary language item, 3) use screenshots of surrounding code and the language's main logo to build stronger context.

The following items were also useful, for building stronger recognition of common coding errors. Brackets are pretty ubiquitous, so just remembering to look for such things is useful.

In general, I use the spell-pad answer component for programming items, because it lets me type them in, which is always good practise.

Mathematics

This is definitely my best achievement in using procedural SuperMemo. Most of my procedural items are mathematical, and the effectiveness of these is very high. I only need to keep a pen and paper near the computer, and I can use the computer calculator to do anything I need.

Below is an example of a calculus question. The key to making this work is writing down the question and solution on paper, thereby simulating how the situation where I would need to use this. I think it's worth experimenting with numbers in place of pronumerals. For example, you could also write this question as sin[k(x)] instead, but I don't think it makes a difference to learning.

The next example shows a more in-depth example. Basically, every time I see this question I need to follow the same procedure, or else I won't get the right result. In practice, the only difference between this question and the previous chain rule question is that it takes longer to solve. Otherwise, it works the same.

The most complex type of item is shown below. Basically, it is the sort of question you would find in an end of semester engineering exam. I am still convinced that if you want to retain the ability to solve this type of question over the long term, that you need to ultimately have an item such as this which requires you to solve from start to finish (same goes for playing musical pieces). Unlike declarative items, I propose that the minimum information principle does not refer to the complexity of the item; it refers to the step-up in difficulty from what you can already do.

Music

I eventually stopped using SuperMemo for guitar and violin because of lifestyle. To me they were much more leisurely activities. I didn't practise as consistently as I would have liked because of work hours rather than laziness. When I did pick up the instrument I didn't particularly want to spend my time drilling skills. However, I think it is worth noting that of the skills I did import to SuperMemo and practise for a couple of years, I can definitely recall these better even now. Hence, if/when I had the time for a more serious practise schedule I would return to SuperMemo.

Rubik's Cube
Although this is hardly important, I thought it relevant to say that I tried to solve the cube two days ago and got stuck. This never happened in the past, but I have not used it for ages. (Note that I was following a specific procedure to solve it, rather than spatial brilliance). Just another data point to remind me of the importance of spaced repetition.

Future of Procedural Learning with SuperMemo
At this point in time I believe that if and when SuperMemo becomes super-portable and mobile-compatible (like Evernote) it will be much easier to overcome the prop-problem. You could just take your phone to the karate dojo, basketball court or music practise room. Until then, only the most dedicated students will continue to use SuperMemo for more active procedural learning. And good on them!