Once you have an agreed goal, you can investigate techniques for reaching it. But some of the disagreements are over what the goal should be. The "invisible in

Once you have an agreed goal, you can investigate techniques for reaching it. But some of the disagreements are over what the goal should be. The "invisible interface" people's goal (in strong form) is to dispense with explicit interfaces as much as possible, seeing them as just friction between what people want and what the computer can do. One version of how to achieve that vision is AI-heavy, relying on people saying what they want in natural language and software like Siri figuring out how to give it to them. The rough opposite is more of an interface-centric approach, where the goal is to actually foreground the interface as an explicit point of interaction, and have it present a logical and coherent set of controls that, rather than being invisible, makes clear "I am an interface and I do X/Y/Z". Detailed information about things such as eye tracking speed seems to me like it'd be most useful in doing the actual implementation, once you have a rough idea of its purpose and use case. It's certainly possible to do scientific investigation of the more general question as well, but it requires more than micro-scale laboratory tests.