Canadian Iroquois-class destroyers reinforce the Falklands screen

What difference would four Canadian Iroquois-class destroyers make in the Falklands War?

They would strengthen the carrier task force's air-defense screen, with perhaps one ship detached to San Carlos Water.

The Canadian destroyers would be a useful addition because they bring further air-defence capacity and more hulls to the screen. Most would probably remain with the main carrier force at sea, where layered defence and endurance were critical. One might enter San Carlos Water, but concentrating all four there would waste their value to the outer task group. Their chief contribution is strength in depth rather than a single dramatic tactical intervention.