Thank you. Will do.
If you're visiting this page from the future in search of why we changed the config, behold Bob Armstrong's plots showing the difference between the measured size of point sources and size of the PSF model as a function of FWHM.
"Coadd" Is the original from S18A warped with the Lanczos3 kernel. It's positive which means that point sources are Narrower than the PSF models. Increasing the lanczos order to 5 moves it to ~ -0.001, which means the coadd point sources are slightly larger than the PSF models. (This is what I would expect given uncertainties in astrometry). Increasing the Lanczos7 makes the point sources even larger compared to the PSF models. We don't understand why this is, and are choosing lanczos5 for its empirical improvement, while we do further investigation