New Patent to Color 3D Printer Filament During Print

We have yet to see a really reliable method of 3D printing with multiple colors with FDM technology. One patent filed recently though shows quite the promise. The patent which can be read about here: http://3dprint.com/4877/patent-color...inter-filament is pretty clever if you ask me.

What it does is send printer filament through a colorizing mechanism prior to it getting heated by the extruder nozzle. This colors it just prior to building with the filament.

Could this work? Do you think we will see something like this any time soon? Check out the diagram of this patent below:
http://3dprint.com/wp-content/upload...3-1024x642.jpg

People have been using markers to manually color filament as it feeds through. I don't think it's outlandish to have some kind of automatically changing the color by changing the pressure from different markers.

That would be good for layer-based coloring, because it takes a certain amount of filament to purge the old color before it's not noticeably altering the new color. This system isn't good for fine detail coloring, like you'd see on an Mcor machine.