I haven't seen that before, but from reading about the specifications of the Colecovision and the Master System on Wikipedia, I remember being struck at how similar they were. As I recall they were almost identical. From what I recall, and bearing in mind the limits of my tech knowledge, it looked to me like the main difference was that the Sega system had a lot more RAM and video RAM. So I'm not too surprised the two could be gathered together in one hardware form.
