I just ran the Battle of Dungeness scenario, to show my wife how Privateers Bounty looked. I commanded the English and set the difficulty to hard. The English tactics were sail as a single group, to have full sails set, and to only turn downwind. The Dutch, under AI control, "came at them". That was a bad move. The English essentially "crossed the T". At 4:07pm, the English had 74% of their fleet left, while the Dutch only had 35%. The collection of large English ships, heavily armed, was sufficient to overcome the "two-to-one" ration between the fleets.
So, why did the English do so badly in the real battle? It wasn't because of Dutch tactical brilliance, as they did not do particularly well, either. The real reason was that the English were timid, largely did not even try close and fight, and did not operate as a unit.
By the way, at 5:17pm, the ratio was 70% of the English versus 17% of the Dutch. It was a fight to the finish, but a one-sided slaughter, not "mutual destruction". A few minutes later, all the Dutch ships were sunk, with no further English losses. What a contrast with the real battle!