The receiver anonymity tidbit was something I recalled from this summary http://fanti.web.engr.illinois.edu/ciss2016.pdf http://fanti.web.engr.illinois.edu/ciss

The receiver anonymity tidbit was something I recalled from this summary http://fanti.web.engr.illinois.edu/ciss2016.pdf http://fanti.web.engr.illinois.edu/ciss2016.pdf which for some reason was in my crypto / chat papers folder..