I bet their color hacks end up doing something weird or possibly nothing with emulators. No idea about the implementation details of any PC emulator, but it sure would be tempting for an emulator to just display the bitmap copied from the emulated machine's display buffer instead of emulating the actual display adapter. Even emulating the adapter wouldn't be enough, I suppose, as the color tricks rely on some unintenional (from vendors PoV) bleed behavior, probably on the analog side of things. So I guess a proper emulator should also emulate some of the analog details of the display itself.
There are emulators (for other targets) which do emulate NTSC decoding properly, but until I did the research for this demo nobody understood how the CGA card generates composite signals well enough to be emulate it properly. I have some code which I hope to be adding to DOSBox (and any other emulators that want it) soon.
