It's easy to understand the people who are rating it low.
It's captured in the video at the 2:16 mark.
They are people who "do tricks".
I suspect they'd have reacted the same way had they purchased Lessons 1 & 2 direct from Tarbell back in the day?
Maybe his way of weeding out the "do tricks" crowd, figuring they'd give up and never order any further lessons? :-)