Outdated charts and Ewen Southby-Tailyour's local knowledge

Clapp reportedly distrusted charts that may not have been updated since the Second World War. A small error in a hill height or coastal outline could decide whether an anchorage was concealed from aircraft, making old survey data an operational hazard rather than a clerical inconvenience. Ewen Southby-Tailyour had sailed extensively around the islands and kept detailed personal notes. His firsthand knowledge supplied landing-craft planners with information that official hydrographic material could not reliably provide. The speakers also recount how Southby-Tailyour helped define the landing-craft command as a major's appointment and then became the obvious officer to fill it. Local experience, hydrography, and specialist authority could matter as much to an amphibious plan as formal force strength.