I was calculating 18 * 16. For some reason I did not refer back to OP. The approach is similar however. I agree: holding values is quite difficult in many case

I was calculating 18 * 16. For some reason I did not refer back to OP. The approach is similar however. I agree: holding values is quite difficult in many cases, but the whole discussion is about this example specifically. You only need to remember 3 values in this case, which should be easy for most people. And no I do not overestimate myself. I usually suffer from imposter syndrome.