For a while now I've been trying to find the relevance of sudoku for academic writing. It must have some relevance, right? It requires some concentration and thus might help with working memory; it could stave off senility in the aged or middle-aged. What I've come up with so far is that it forces you to look for what's not there. In other words, in a row, a column, a square, you have to see what number is missing, not what number is already there. Secondly, you have to think diagonally. Your aim is not to make a column of ones, but a pattern of ones or twos or threes where none of these repeat.
Look at a classroom of students. You see who's there. What's harder to do is to see who isn't in class, because there is no visible evidence of those students. You might look at a chair and say, who sits there, usually?