What an early teardrop hull would change for submarines

How would adopting a teardrop hull after the First World War have changed the Royal Navy's submarine fleet?

It would improve submerged speed and diving, but conventional boats still needed good surface performance, so the tradeoff remained different from the nuclear-submarine era.

Adopting a teardrop form after the First World War would likely have produced faster submarines with stronger deep-diving performance. Interwar boats still spent much of their time on the surface, so underwater optimization was not the only design goal. Two competing development paths existed rather than one missed solution. The later U-class lineage represents a different attempt to balance an efficient hull with the operating pattern of a conventional submarine.