BrainOfJ: Reading spaces = thinking room?

Just re-discovered this post from 2004 (BrainOfJ: Reading spaces = thinking room?), which suggests that Charlemagne started a revolution in communication by introducing spaces between words. Spaces enabled silent reading for the first time, separating writing from speech and contributing to the fall of the priestly class's monoploy on literacy.

The historical claim probably goes too far (historians: what should I read on this?), but it seems to me that focusing on a bodily enabling condition for a separation between writing and speaking might provide a starting point for re-introducing the body into Derrida's philosophy of the text.