All of that involved consciously causing physiological changes in your body for the computer to sense. Suppose this was a thought interface for an aircraft pilo

All of that involved consciously causing physiological changes in your body for the computer to sense. Suppose this was a thought interface for an aircraft pilot. Physically they're already fully engaged in a demanding activity, what we need is to open up a new channel of communication from them to the computer in addition to their physical input. If they're focusing on twitching or changing the resistivity in their fingertips, that's going to interfere with their using their fingers to manipulate controls. There are other similar situations, such as people in a coma that can't cause physiological changes. The point is to offload as much processing on to the computer, to make the process of communication as simple and direct for us as possible. Training ourselves to jump through mental and physiological hoops is the opposite of the point.