I believe she made a mistake here: neural signal latency to toes would be nearly double that of latency to fingers.

I disagree: I find that she makes an excellent point about the choice she made in the video linked above. She is a designer, exploring ideas about body augmentation. She is not (and nor is anyone else) at the stage of perfecting a design so that it become the most performant. "Premature optimization..." and all that.

From your comment is sounds like you actually agree :)