1.) unity may do that, but it's incorrect on a technical and physical level. Emissive pixels are considered to pass without lighting/shadowing. They can also give off illumination based on their brightness, depending on the engine (and usually they're great in combination with bloom, even if they don't give off…
I'm not entirely convinced it matters that much, yet. I haven't really seen an example where it looks objectively incorrect, and at the very least should be good enough for a "preview" of sorts at least for now.
i'm interested in using this as well, however i get this in max 15 with the example you provided. im loading it like i would Xioulin shader so if this is a error on my part my apologies, i know at least one of my buddies would love this kind of option in max aswell. best of luck i will be following the development of this…