It's the main lane where all coastal traffic passes, and one of the most dangerous and weather sensitive regions on the lane. Larger ships sail farther out when weather conditions don't allow for sailing the coast, but a lot of traffic including fishing vessels carrying fresh fish simply have to wait. So it's not as meaningless as geography makes it look.

Not this specific route, but it would be very useful for the Hurtigruten ships that serve the entire Norwegian coast (mentioned in the Wikipedia article, actually the ship shown in the tunnel cross-section has the Hurtigruten livery: https://en.wikipedia.org/wiki/Stad_Ship_Tunnel).

as i understand it, the problem is not getting to Åheim, but sailing along the coast, where, in this part, the conditions are frequently bad. the tunnel is not a shortcut to Åheim but a detour passing Åheim to avoid the coastal area and instead sail through the fjords.

From Wikipedia:

> The Stad Ship Tunnel (Norwegian: Stad skipstunnel) is a planned canal and tunnel to bypass the Stad peninsula in Stad Municipality in Vestland county, Norway. The peninsula is one of the most exposed areas on the coast, without any outlying islands to protect it from the weather. The section has traditionally been one of the most dangerous along the coast of Norway.

> The surrounding waters, known as the Stadhavet Sea, is the most windswept part of the nation's coastline and is stormy around 100 days of the year, leading to ships often waiting days to pass through.[6][7] Currents, created by the area marking the meeting point of the North Sea and the Norwegian Sea further complicate navigation: Since World War Two ended, 33 deaths have occurred in maritime accidents within the Stadhavet Sea.[5] The official Visit Norway website has claimed Vikings would drag their boats over the peninsula to avoid crossing the dangerous patch of sea.