Coastal motorboats versus battlecruisers

Shipping lanes just outside the coastal guns would still lie within reach of small British attack craft operating from Helgoland. The loss of crews would remain serious, but the strategic calculation turns on replacement cost. Britain could rebuild dozens of coastal motor boats far faster than Germany could replace one battlecruiser. Trading inexpensive craft for a capital ship would therefore favour the Royal Navy even at an uncomfortable tactical price. The threat would make supposedly safe routes around the island another layer of the attritional defence.