What George R.R. Martin Can Teach Us About Tool Selection

I'm always interested in what tools highly successful people use to do their work. While the tool itself can't magically do the work (as Seth Godin reminds us), top performers have usually thought more about tool selection than the rest of us, and we can often learn something from them.
Exhibit A is George R.R. Martin, author of A Song of Ice and Fire (on which Game of Thrones is based) and one of the most successful living authors. George R.R. Martin does all of his writing in a program called WordStar.