Turns out there is a reason I haven't seen any fair-isle or stranded pi-shawls. As soon as I got to 24 rows between increases it became obvious that the work wouldn't stretch properly. The patterns disappear after 7 rows as the stretch required reveals the colour carried behind. Oh well, live and learn. Two layered throws will be warmer than one multi-coloured one, and as a bonus, a lot faster to knit.
Going for a simple one in cream (knit 2 tog, yo) worked every 6th round between the increases.
The brown one I'll look up some interesting lace patterns for (or maybe just use the lovely hemlock ring blanket from Brooklyn Tweed).
Entertained myself whilst knitting with The wonders of the solar system. if I had known 20 years ago how much fun you can have with a physics degree I wouldn't have dropped it for economics!