Routine zigzagging would have made Japanese long-range torpedo attacks against American formations harder to set up. Repeated course changes could have forced destroyers closer to their targets, increasing the chance that American lookouts or guns would catch them. American commanders did not expect submarines nearby and underestimated the range of Japanese destroyer torpedoes. British practice grew from assuming that an unseen submarine might always be present. That precaution also slowed the formation and demanded steering systems and crews able to change course continually.
Notable Point · 6:17-8:20
Zigzagging complicates long-range Japanese torpedo attacks
British anti-submarine habits provide a counterfactual test of Japanese long-range torpedo attacks on American formations.