My sister uses the schizophrenic pattern shown in the middle that uses all the dots. Because sliding your fingers between two dots just pixels apart was an error prone nightmare, she decided to just hop her fingers from dot to dot, based on the fact that if you touch one dot and then you touch another, when you lift the first finger the path between both will be automatically drawn. That way, the trace in her screen is just fingers over dots, making it impossible to tell which one is the first and which one comes next.