Calculators don't really help you think. You need to have a concept of the calculation beforehand and you only run the technical steps on the calculator. Writi

Calculators don't really help you think. You need to have a concept of the calculation beforehand and you only run the technical steps on the calculator. Writing is different. It is more akin to the left leg, when the right leg is your thinking. I am a weird combination of an author and a mathematician-turned-programmer, and both these skills are very useful in either activity; I wouldn't be able to program half as well if I didn't dump my messy ideas to a doc first, especially when the model is far from straightforward. Writing things down is a huge feedback loop for thinking. Plenty of edge cases stick their head out of the doc once you write everything down.