Speed Knitting - How did the old knitters do it? And what is swaving?

I love reading books on the history of knitting. I bought a copy of
'The Old Hand Knitters Of The Dales' by Marie Hartley and Joan Ingilby on Amazon. 

 

Their description of the speedy method of knitting in the Yorkshire Dales included the word 'swaving' which modern researchers relate to the local dialect word for swaying. But it is not known exactly what 'swaved'. 
 
I was fascinated by the similarities on the techniques given in Mary Wright's book 'Cornish Guernseys and Knit-frocks' which I have owned for over 30 years.

 

In both the Cornish and Yorkshire knitting histories, children learned to knit speedily in knitting schools. No doubt, a mother needing to knit her quota each day did not have the luxury of time to teach children the special technique, which would have entailed months if not years of monitored supervision. 

There is agreement in several sources that the professional knitters knitted exceedingly fast and I am attempting to rediscover the method. I am delving into the historical publications.

The rapid clicking of the knitting needles can be heard announcing the knitters proximity! - "Mr Nicholas of West Looe recalled the distinctive clacking noise of needles struck at speed, which could be heard 'before you turned the street corner." from Mary Wright's book.

Mary Wright says, "Experienced knitters achieved very high speeds of about 200 stitiches a minute!" "Mrs Crabtree remembers that her mother could knit a jersey, or frock, as they were called, in a day ... " write Joan Ingleby and Marie Hartley. These two descriptions, written at opposite ends of England, each support the other's assertions; therefore I am tempted to say neither was exaggerating! 

How could the knitters of old reach these speeds? And what was the process of knitting that each region developed? And what is swaving?

I have been researching all the hints which explain what their high speed knitting could look like. More soon ...