For Real?

Here's the next project I am contemplating, the white cabled turtleneck on the right from the latest Rebecca. [Sorry for the tiny picture.] However, after reading the instructions, I noticed something strange. For the smallest size, it requires 950 grams of GGH Goa! The two men's sweaters in the issue only require 750-900 grams of yarn. That means I would need 19 skeins of Goa. I think that this must be an error. I've emailed Rebecca, but have received no response thus far. What do you think?