I'd really like to be able to have more control over manually pulling the protein, and I was thinking that two mice could make it easier.

One mouse could hold a piece still while the other pulled.

Or, one mouse could be used to rotate, and the other could pull (for simulatenous rotating/pulling).

Or, you could pull with both mice at the same time.

I have this constant urge to involve my other hand while I'm manupulating the protein, but there's currently no way. :)