The proposal did not turn out to be nearly done, and Fergus and I re-wrote it on the weekend and today. But we must submit tomorrow, so the end is in sight.
I spent a bit of time following up some of the z-band-only sources in the SDSS Southern Stripe. Most of them are spurious in one way or another. The dominant source of spurious sources is artificial satellites and other fast-moving objects. In particular, some of the strangest sources Lang had found so far turned out to be individual blinks from a blinking artificial satellite.