Could old boilerplate or other improvised spaced armour have protected the pre-dreadnoughts?
Short answerA dry-dock conversion could have added a compartmented outer bow and hull structure, serving the protective purpose described as torpedo bulges.
NotesThe suggested protection would require dry-dock work. A compartmented outer structure could be built around the bow and hull, with torpedo bulges used as the comparison. Wood is doubted as a suitable material. This remains a proposed modification to the ships used in the assault.