Can't see the forest for the trees? What's the difference between dark blue and light blue? Shade, hue, contrast. They are the same pigment, but different color.
IMO strictly/exactly defining how a FOXTROT should look is the height of artistic arrogance and conceit (think about it). IMO Alex Moore understood that, and he also understood that for the art to evolve, there has to be some freedom or leeway in the magnitude of movement to promote artistic EXPLORATION and expression.
So he created a framework, instead of a rulebook.
Sure, a heel lead may be the same to you between a Waltz and Foxtrot. And sure, you may interpret Alex Moore's codex in any way you want.
AGAIN, at the end of the day, No matter how you think that that movements are the same doesn't really matter, does it. Because HOW you execute the movement will dictate if the dance you're doing looks like a Waltz or a Foxtrot.