This pattern had several rethinks while in progress. The outcome is a hybrid of yoked jumper and standard hoody, having a kangaroo pocket and a hood, with a yoke that has been steeked to fit a zip. The fair isle pattern is made up of mathematical symbols - infinity, binary, approximately equal and field range - as a small joke for the recipient.
I think it is the best thing I have ever come up with and I have blogged the pattern so I can do something similar again, without having to unravel half of it.
The yarn I used was my hand spinning from the Tour de Fleece, double knitting weight on average, if not entirely even.