Does this touch bar work on the principle of "conductivity" that requires skin contact? Like the surface of the iPhone? Or is it pressure sensitive. For example, could you operated it with the eraser end of a pencil. I ask this because I was planning on updating to a MacBook Pro when they come out but I'm paralyzed from the neck down and I use a typing stick by mouth that has a rubber tip to type with as well as operate a trackball, remote control, phone Etc.… I know there are mouse sticks out there with tips that operate iPhones and iPads by conductivity but the tips don't work very well for typing and working a trackball remotes and such because they're too slippery. This requires a rubber tip to have some kind of grip to operate devices. If the touch bar works on conductivity I don't now how I would be able to use function keys.