I think the way this would work is you would have your Canadian friend/owner drive it across and then return via another mode of transport. It's entirely possible you could get away with it pretty much indefinitely (especially in an area where folks are used to seeing Canadian plates), but I could also see someone checking a list of "foreign vehicles that entered the US and never left" at some point and one or both of you having some explaining to do (i.e. being ruled inadmissible).