This study of the book of John is definitely on the challenging / demanding side, but if you're willing to put in the work, you will likely come away with a much deeper and richer understanding of the Gospel of John. Some things she particularly draws out are all the connections to the Old Testament, the trinitarian nature of the book, the rich symbols and imagery, how Jesus ministers to different people as individuals, and the overall purpose of the book as expressed in John 20:31.