Thompson then begins a discussion of physical attributes of the graphic style used in the four manuscripts. She warns against superficial examination by noting that similarity of layout can be deceptive and that one must thoroughly analyze various characteristics such as margins, rulings, scripts, corrections, and annotations. In her 2001 article she focused on ruling and music script. She notes how each of the manuscripts have a relative small ruled area ranging from 55.6% (for the Fitzwilliam Virginal Book) to 58.8% for Egerton 3665), observing that conservation of paper was not an issue and that these scores must have been intended for presentation. She based her observations on the principle that similarly ruled paper would have been created at the same time. She notes this is consistent for the Fitzwilliam Virginal Book and Christ Church MSS 510–14. It is not true for both Egerton 3665 and Drexel 4302, leading her to conclude that these two manuscripts were not planned as single units (which would have had identical ruling) but portions made at different times.