G3: concentrating armour, machinery, and dockyard needs

Grouping magazines forward and machinery aft shortens the propeller shafts and reduces the thermal boundaries needed to protect ammunition. Shorter shafts save weight and reduce wear and maintenance. G3's compact hull would have been shorter than Hood and easier to accommodate in existing dry docks. Expected infrastructure improvements in 1916 and 1922 had become unavailable or unlikely, leaving the Royal Navy planning to use its existing facilities until 1928. Space between the principal magazines and hot machinery also makes ammunition temperature easier to control.