Interestingly, my mother (who is a mathematician) absolutely loved it. Still does. She exclaims over the tidiness of organizing a sentence into neat little artistry. I think it was the logic of it all that drew her in. I found her predilection odd, though.
Still do. And I still think diagramming is a waste of time. And so do many others, apparently, according to this NPR article. What about you? Were you made to diagram as a student? Did it help? Leave a comment!