I went to this website:
and found this:
Short Note on Andean Knitting
>I have been reading Cynthia LeCount’s book “Andean Fold Knitting”. There
>lots of photos of knitters who carry the yarn around the back of their neck
>to keep the tension. The problem is that the photos don’t give any
>indication of how they work the thread in their hands. Does any one know
>what exactly it is they are doing? I knit VERY loosely and would love to
>learn to knit at such a close gauge as the examples in this book.
Andean knitting is a bit different from European/North American knitting. It’s actually purling. If you look closely at the photos, you’ll see that when they work “in the round”, they work (purl) on the side furthest from the body, rather than knitting on the side close to the body, the way most westerners do. The stockinette stitch side faces outwards.
The yarns are moved into place with the thumbs, which is said to make changing colours very easy. The purling position and the tensioning around the neck contribute to a very tight tension and result in a densely-knitted fabric. Remember that they also re-spin their commercial yarns so that the yarns are tighter and denser.
If you have Knitting around the World from Threads, the final article on different knitting styles demonstrates Greek knitting, with the yarn around the neck. I once knew an American-Italian student who tensioned her yarns the same way. This is the closest I’ve seen to Andean knitting style. If you want to try it, I suggest that you try 00 dp needles and fingering weight yarn and practice purling on the far side of your circular knitting.