Re: Multi-modal communication

I've done what you describe also - had two, parallel and separate,
conversations at the same time - one in ASL and one in English.

I've also had conversations parallel and identical in the two modes -
e.g. when in a conversation with a deaf person and a non-signing
hearer.

(For that matter, I've done that between ASL and Russian, which was
even weirder...)

However, that's not what I meant, nor is (AFAIK) the Herbert version.
What I am interested in is multimodal communication where the modes
are intertwined - neither totally separate nor merely redundant; i.e.
the whole is more than the sum of the parts. I've not seen anything
that's like that beyond the absolute most basic level.

 - Sai