> I believe it to be the opposite, the chances of you just guessing 10 correct answers in a row is ridiculously low. It encourages you to make sure every answer is correct before submitting it, otherwise you would have to start over again.
That's not the point. You can learn to solve ten math problems in a row by simply memorizing algorithms to solve the problems, rather than learning the underlying concepts. The author criticizes Khan Academy because its methods emphasize the algorithms, rather than the concepts.
There's a good bit of research suggesting that the ability to solve quantitative problems isn't necessarily related to underlying qualitative understanding. Students could benefit from teaching methods designed to promote understanding.