Still here, not offended.
I think you will find it in some of the Nikon literature, for example. You can start off from Nikon Raw, and works in sRGB and 12bit , and get a very good range of colour, but the text books will show you where colours are outside the system and cannot be shown, even then.
But when you switch to jpeg, and in particular for eMail or internet transmission ( as distinct from colour printing, or sending a file for subsequent handling) you hit the buffers of the 8 bit system.
It may be that the system you describe is specifying a blend of two or more colours.
Or it may be that I am out of date ! My photographic technology dates back to the last century when I was an active exhibition photographer.