This would work for an idle screen but I can't imagine this would be very efficient for real use, unless the hardware cursor is put in some other framebuffer (I assume it's not otherwise the author would have probably mentioned it?)
on computer timescales, humans are basically motionless, as long as there is motion, you do the 60Hz update, occasionally you take a page fault too, not a high cost compared to a screenfull of colorpsace conversion. But when display is not changing you save a lot of cpu power.
But also Wii has the gpu abilities to trivially support hardware cursor
saves a lot of CPU