Why British torpedoes were suited to Taranto's shallow harbour

Why would the British still lead the torpedo attack at Taranto instead of leaving the harbour strike to Japanese aircraft?

British air-dropped torpedoes had the specialized shallow-water entry system proven for Taranto, whereas a deeper dive would send many weapons into the seabed before they could reach a target.

The first requirement is for the weapon to reach the ship at all. British wooden fins and a tension wire controlled entry so that the torpedo belly-flopped and settled into a shallow run. Japanese and American weapons used fins, while the full British method added the tension-wire arrangement developed for the harbour attack. Detonation failures still matter, yet losing a large fraction of weapons to the bottom before they approach a target produces an even steeper reduction in effective hits.