copper us$3.35/lb, page-4

The studies I refer to are the ones showing that, on average, mutual funds following a special investment strategy (and paying fund managers millions for their expertise) do no better than index-linked funds.

Your strategy of buying when there is good news or selling when there is bad news (directors buying/selling being an indicator of good or bad news) would only work if you could act on the information faster or better than anyone else. The SP will immediately move in response to news, and if it doesn't move in the direction you expect, you have to ask what it is that you're missing. Sometimes you will decide that you're smarter than the market and you will be right, but just as often you will be wrong.

This is a nihilistic view of markets. I still think that I can rationally pick undervalued stocks. I agree with you that ESG is undervalued, so I've bought ESG shares, and now I'm looking at the reasons in favour of buying HGO. But I have the nagging feeling that I may be fooling myself.