I’ll give it a read but my initial sense is this paper probably has a big grain of salt attached to it.
Individuals are likely to perform worse than professionals and the data is likely harder to verify. In what other industry do we believe amateurs are better than professionals? If Individual investors can consistently beat the market, Wall Street would send a dump truck full of money to hire these people.
The bottom line is for the people I write for, picking stocks is a bad idea and the thought that someone can take some course online and learn how to beat the market is snake oil.
Invest in the index at the lowest possible price, and focus energy on making more money that you can invest.