Transports under coastal warning

The episode makes the final crossing look less like a single heroic dash and more like a vulnerable movement under sustained harassment. After attritional fleet battles, frigates could become the most important warships still available in numbers. Britain probably had more of them and could concentrate vessels from Chatham, Plymouth, Portsmouth, and other commissioning dockyards. Those ships did not need to defeat Napoleon's army; getting among the transports or repeatedly attacking the convoy could disrupt the crossing. The watch point connects dockyard geography and fleet depth directly to the survival of the invasion's troop and supply vessels.