Yes, interesting article.
A couple of thoughts - a lot of people ask OP's for details of their active investing strategies when people talk about active investing - well, here is a good example of front running stocks that are being added to indexes.
Also, I think there is too much focus on expense ratio. Expense ratio is not what makes your balance go up, it is total return. Sure, a higher ER makes the fund work harder to get the same return as a fund with lower ER but there are actively managed funds that do it on a consistent basis; one example being FGCKX. So, sure, look at ER but make sure you compare total returns also.
PS - Yes, I've read many posts here and articles elsewhere discussing passive index vs actively managed; that what is top 25% one year won't be next year, etc. Just mentioning that to save people having to re-post same info. I have a mix of both passive and active funds . . .