The quality of decision making in any company is undoubtedly a critical success factor. Numerous studies have shown that richer decision making occurs with a diverse leadership population.
Companies that have an all-male board, or a male dominated board, could find that decision making is governed by tradition and rules yet, when the pressure is on, men can become more eager to take risks (to get rewards) and decisions may end up being driven by the egos around the table.
Whereas research shows that when the gender balance is mixed, the decision making is often more considered. Female directors tend to be more co-operative and seek collaboration. This might make them more risk adverse, but it also means they take more time to weigh up the contingencies and consequences.
Is one strategy better than the other? Not particularly, which is why it is good to have both men and women at the top level so that your company can benefit from richer decision making.