The andi06 track eraser isn't just 'invisible track', he has a 'spline eraser' as well. Specifically on his trackside kits - tunnels, stations and junctions, using the 'eraser' removes track (or a spline) attached to an object, it doesn't just replace is as 'invisible track' would. You can prove this be adding a second track after using the 'eraser' - you don't get a junction and a lever as you would if you'd used 'invisible' track: The original track (or spline) isn't replaced by the 'eraser' - it's removed. It came about because sometimes track - or splines - attached to a scenery object won't delete if they are inadvertently attached to the wrong node - attaching an 'eraser' removes the errant spline/track...
So difficult to explain - so easy to use once you get your head around the difference - took me a while too....