I discovered a new AUTOLIFT-HOTEND

This hotend lifts itself automatically for something like 0,5 mm when you retract the filament.
It uses a spring mechanism and micro-linear-bearings for that.
I think this could make 2 - or more - colour - printing, especially for larger objects, finally possible without the problems we actually have (scraping inactive nozzle, etc.).
Well, it´s quite expensive, but it could be a great update if it works.
I found something compareble here: http://www.youtube.com/watch?v=ARifgeNJ99E
But I didn´t find out more about this modell yet (Merlin Hotend).
What do you think, can this work? Do you see any problems at the mechanics?