I resonate with the author preferring to read an e-reader than a book when their mind is more amped up. Why is it easier to read from a mutable screen than paper when I'm frazzled?
If you like to read to help get tired for bed, I would think a book is the best method. Certainly works that way for me. I can't even read in the middle of the day because it makes me too drowsy and sometimes knocks me out entirely, then I lose like two hours before I awake from that unintentional nap.