Are you simply saying that quaternions can be used to perform the same rotation as the Euler method or are you saying that the rotation information along the Eu

Are you simply saying that quaternions can be used to perform the same rotation as the Euler method or are you saying that the rotation information along the Euler axes can also be lost even when using the quaternion method? Said another way, are you conflating gimbal lock the physical property, with gimbal lock the common bug of creating irreversible rotations or is the bug still possible?