No, what peterguthrie is referring to is basically mipmapping in a texture format. Multiple resolutions of the texture are stored in a container (exr or tif), and the renderer then uses smarts to choose the correct resolution inside the tiled image based on distance to camera, and thus is able to efficiently use RAM resources. The user is also able to bias the resolution chosen by the renderer by changing the blur value if they want to.
In a perfect world, I'd love for Corona to be able to load in tiled UDIM's for the most efficiency in memory usage and shader setup.