John Beardsworth on Lossy DNGs
I think there is definitely an issue of file management lurking to bite the unwary photographer. If you are happy to downsize your DNGs then you need to be aware of which files are affected. Application UI is one way, and file naming is another.
I can’t see myself using Lossy DNG for downsampling files, but as mentioned in passing by John, I can see myself converting iPhoneography created imagery to the Lossy DNG format, and then nothing is lost.