We need to know what he put the money into. Only knowing one side of their trade doesn't tell us anything. A comment like "It's up 25% of his sale price in the

We need to know what he put the money into. Only knowing one side of their trade doesn't tell us anything. A comment like "It's up 25% of his sale price in the few days after he sold" is nonsense unless we know he didn't invest in something else up 25%! Even in our own investing we should be comparing A versus B - not looking at A alone. And generally most talk about stocks has this problem.