I agree, I don't believe this would pass a test for statistical significance (of outperforming the market indices).

Unless there is a way to break this data down much more finely (by 6-day window, by individual asset) in which case it's possible there's a high p-value but low-power effect. Even so, if there are more than 100 experimental firms, a single one with p-value .01 isn't evidence enough to jumping to big conclusions.