A customer has asked me what, if anything, I know about how to knit sipalu. I have spent a LOT of time on-line trying to find out anything I can about sipalu, and the ONLY reference I have found to it is the pattern by the same name from Knit Picks. "Sipalu" is Nepalese for "skilled" or "clever". It seems to be intended to describe Fair Isle projects with a distinctly "Himalayan" design. I would hazard a guess that virtually anything Fair Isle with an East Indian, Tibetan, or Nepalese sort of patterning could be considered sipalu (emphasis on the word "guess").
Having said that, the swirled and symmetrical designs of the Knit Picks bag resemble some traditional Nepalese art. Thus, I am extrapolating that sipalu knitting involves a) Fair Isle technique and b) replicating the traditional, symmetrical designs of Nepalese art, especially the mandalas Tibetan monks are famous for drawing with colored sand. Other examples of this art can be found here.
This is good news, to those of us with a particularly masochistic bent towards doing our own color charts.