I admit I am no historian, so forgive me if my comments are incorrect or out of context.
It was my understanding that the Muyejebo (predecessor of the Muyedobotongji) was a trasnlation of the Chinese Ji Xiao Xin Shu. This text covered military tactics, formations, and field drills.
As I recall, the translation only really addressed the field drills with weapons and empty hands. Additional material of Japanese martial arts was also added to the text (Muyejebo).
I own a copy of the Muyedobotongji, and I honestly have a difficult time gleaning any information from it (probably due to the lack of historical context in which it is written). However, it is still my understanding that the manual is mostly about field drills with weapons and empty hands, not necessarily about a martial art.
I am interested in the context and usefulness of the Muyedobotongji, as well as Sibpalki, so any light you all my shed on this topic is much appreciated.