Where in Canon's website did you get the information about the number of aspherical lens elements in the lens?
I don't even know what to believe anymore. I find too many inconsistencies between Canon's different regional websites. Canon USA says the 10-18mm lens have an "enhanced coating" that helps resist flare. Canon UK says the 10-18mm lens have the Super Spectra coating.
From the CanonUSA site:
There is a possible contradiction though, in that the write-up for the 10-18 only mentions 1 aspheric lens: