In one of the videos on KP she talks about that (rapid eye movement)...
It would come in handy during the holiday times or that never ending afghan
I did like one of her tips, I hold my left index finger very far out...she mentioned that puts a strain on those muscles and I do get sore after I knit for a long spell...so I'm going to try and hold it closer, not sure I can hold it as close as she does though...