My response to KenV got lost. While some torpedoes such as the lightweight ones can be noisy at high speed it does not follow that all torpedoes are noisy. There are also other means of detection.
Other issues are the self damage to the delivery vessel, how to navigate the torpedo to its target, being certain that the fleet is active in the target area.
The delivery vessel would vulnerable to prior destruction unless use of the torpedo was the first enemy action.