Why were the fast Abdiel-class minelayers not used as the basis for large fleet destroyers?
Short answerTheir high-performance machinery made them too expensive for that role.
NotesThe minelayers' speed and gun armament invite comparison with a large fleet destroyer. The direct objection is cost: achieving that performance requires an unusually expensive machinery installation. A projected successor illustrates the scale, pairing about 5,000 tons with 160,000 shaft horsepower. Such ships could meet a specialist need, but the same approach would make routine destroyer construction costly.