I started this during the opening ceremonies on February 12, then ended up unraveling a week's worth of work and starting over again on February 20. I'm really glad I just bit the bullet and re-started it in the smaller size on larger needles, not only because I then had just enough yarn to finish it, but also because the resulting fabric was much more wearable, with a much better feel and drape.
I finished the knitting and grafted the hood and underarms and wove in all the ends on March 3. I had to go out and buy a single wooden toggle and knit an i-cord loop to fasten the cardigan at the neck and I finally did that on Saturday the 6th.
So yeah, if I had started out at the beginning of the Olympics with the needles and size I ended up with, I would have certainly had this thing done by the closing and had my medal. Lesson learned: swatching is good.
Now I really can't wait to start one for myself!