In the morning, Juna Kollmeier (OCIW) gave a great talk on the intergalactic radiation fields (called "metagalactic" for reasons I don't understand). She has found a serious conflict between what is computed by any reasonable sum of sources, what is inferred from the outskirts of galaxies, and what is needed for local IGM studies. One possible resolution, which she was not particularly endorsing, is heating from dark-matter decay or annihilation. Neal Weiner (NYU) loved that idea, for obvious reasons. During the talk, several good project ideas came up, some of them related to the kinds of things Schiminovich has been thinking about, and some related to SDSS-IV MANGA data. Kollmeier convinced us that a next-generation experiment will just see the IGM!
After lunch, Bob Kirshner (CfA) gave a nice talk about how much more precise supernova cosmology might become if we could switch to (or include) rest-frame near-infrared imaging. He endorsed WFIRST pretty strongly! He also agreed explicitly that getting more SNe is not valuable unless there are associated precision or redshift-distribution improvements. That is, the SNe are systematics-limited; hence his concentration on infrared data, where precision is improved.
Late in the afternoon, Vakili sketched out a fully probabilistic approach to interpolating the point-spread function in imaging between observed stars (to, for example, galaxies being used in a weak-lensing study). Again with the Gaussian Processes. They are so damned useful!