I'm an educator by profession myself (though not in dancing, i hasten to add).
Text books are written by humans. When i recommend text books to my students, i'm acutely aware that they all have their faults (the books i mean!).
I think the problem is that the text books simply are not rigorous in their definitions. Having the last step of one figure being the first step of another figure is bound to cause confusion. Confusion slows and undermines the learning process.
By the way - German teacher - your posting was excellent