The theory was based on the fact that this book has descriptions which are hard to believe to be the ones of those days; for example, although Rikyu's days put a premium on chaire (tea container), the book says, 'Nothing is more important than Kakemono (a hanging scroll; a work of calligraphy or a painting which is mounted and hung in an alcove or on a wall).'
その根拠は、例えば茶入が重視されていた利休時代に「掛物ほど第一の道具はなし」と記すような、当時のものとは考えられない記述が目立つ点であった。