Right. Just to clarify, your destroyers and combined fleet can happily sail right past enemy subs and transports. You need to spend 8 IPC on a destroyer to use it as a speed bump. Even then, you can destroy the blocking destroyer with air and a sub maybe, then non-combat move past that contested sea-zone leaving behind only the sub and the attacking air units non-combat move to where the fleet will end up. It gets even harder to slow down a multi-national fleet, your ally clears the blocker then you can move 2 spaces and do combat before a new blocker can be placed, unless the defender was also multi-national….
