It's probably not quite clear why I am doing these "Cube Drills" and what they are so here is a little 2AM insomnia-fueled rant.
Basically there is two approaches to art: "Top-Down", which is perception based, and "Bottom-Up", which is based on construction.
All my experience in art comes from the top-down approach, I would either have a reference or would first visualize the final end product in my head, then perceptually try to replicate that end result on the canvas. There is no construction, it just goes from rough blobs of color to less rough blobs of color, fixing mistakes over time. This can be a extremely effective method in the hand of a seasoned art veterans, but for your average Joe artist the results will be very inconsistent.
So I completely lack any experience in the bottom-up approach of drawing which makes learning perspective a extremely daunting task where I can't even wrap my head around the simplest concepts.
This is where the "Cube Drill" comes into play. These are not to be confused with the "Draw-A-Box" exercises, which I still think are completely pointless.
The "Cube Drill" is just a practice to break established thought patterns about drawing and get yourself accustomed to bottom-up drawing by focusing on the simplest three dimensional thing you can draw: cubes. You start out with just filling out a page with cubes, it doesn't matter how they look like or how they are organized. Then you let your creativity flow free and do more things with those cubes, you start stacking them on top of each other, taper them at the end, draw them with holes, start constructing spherical connections, going wherever your mind goes. The only restriction is that the end product should be three dimensional in some way. In the past 8 days I have filled about 19 pages with very loose sketches in this manner and I will probably do another 21 pages at which point I think I am sufficiently prepared to study the mechanics of the different joints and do a similar "Bone-Drill", slowly raising the difficulty.