The story of "Bean," a free word processor for Mac OS X
bean-osx.com
bean-osx.com
That definitely resonates with me.
Unless of course the author is talking about mixing pigments from flowers and such with a binder then painters really don't need to mix their own pigments for any understanding.
It affects how the creator works, which indirectly affects the resulting work. However, it doesn't directly affect the actual output.
The novel, when printed, could be laid out and paginated differently, printed using different fonts, with no trace of the word processor used to create it.
A painter mixing paints could be to achieve a specific color or texture. The equivalent of that for a novelist could be studying word origins or creating a new language or new words (Tolkien?).
It never hurts to understand how your tools are made and how they function. In fact, it most likely helps you create better work in the long run. At least, that is my interpretation.
The Bean guy is right that it can be rewarding to make a word processor that works exactly the way you think. Even if it's not strictly necessary.
Word gets opened up afterwards when I know that the doc is going to get much larger and complex.
An overview from Apple: http://support.apple.com/kb/HT2523