I agree with many things he said throughout his Ted Talk.
First being when he explains his first day of design school. His teacher writes the word Apple on the board then draws and apple and explains that you can show one or the other but not both. Showing both the words and the image are treating your audience as a child.
While designing my book covers I really took an influence of the things Kidd spoke about. He expressed how designing a book jacket there are three components: the reader, the publisher and the author. You should be designing a book jacket to have a reader pick up the book and say "Wow! I have to read that!"
He expressed that a book cover designer has to be an interpreter of the story.
I feel this is true in all design.
