I've taken a few of his online courses and he does an excellent job telling someone they don't know js, without coming off arrogant. I think it's mostly because he can explain most issues in depth but as a previous comment pointed out, it isn't really a beginner series. Although, I am not sure "[learning] javascript" necessarily means that the learner is completely inexperienced.

I get the understood meaning - I was just making a joke. :)