Why small destroyers still matter in convoy work

Could small Norwegian destroyers have been useful to the Royal Navy?

Yes. He sees them as useful coastal-convoy escorts that could have freed larger British destroyers for more demanding work.

Warships cannot be judged only by their size or prestige. Norwegian destroyers of roughly 700 tons were modest, but their range and armament could still suit East Coast convoy duties. Using them there would release larger British destroyers for ocean escort or fleet work that demanded more endurance and firepower. Effective force structure matches available ships to an appropriate task rather than assigning every role to the largest ship available.