That's pretty good information. You don't really need any more info if you already have a basic idea of tillering.
This take seems more recent than the 40-50's magazine articles, although it covers the classic flatbow that definitely comes from this era. Purpleheart, and ipe whilst available were only rarely used at this time for bows. Original era bows when not made from yew or osage, were nearly always lemonwood as it was so plentiful. They didn't use oak commonly for this type of bow until the modern wood bow renaissance, Comstok, Tim Baker etc.
I do know what Pat is talking about. There are several articles of this type, in the publications he mentions, that are no doubt heavily influencing the current diagrams design.
Here's one that's similar, though the design is slightly different, longer top limb, shorter fades.
https://www.vintageprojects.com/sites/default/files/articles/Flatbow-plans.pdf