There are lots of schedules, it depends on what species you keep (that schedule wouldn't work for a Jackson's, for example), the type of supplements/brand, how well you gutload, and how much natural sunshine your chameleon gets, for example.
So while that schedule works for veileds/panthers, it wouldn't for my Meller's for example. They get daily sunshine so I skip D3 completely from their diet. They get calcium sparingly and a multivitamin about once a month.
So it isn't so much about controversy, it's just that a lot of factors go into supplementing. That's an easy schedule for a newbie to follow, but when you understand what your chameleon needs and what each vitamin/mineral does in the body and in what quantity you have a lot of room to play with a schedule that meets your needs.