The first, "the pattern of electrical potential flowing through the laptop's metal parts..."
What about multitasking, that would change the feedback, though I am confused why there would be electrical potential through a heatsink, that's why I am saying feedback.
Also the last method, audio, vibrations. Multitasking? Dynamic overclocking, couldn't that easily modify the 'system noise' so much that there is no way to know what is going through the CPU registers?
Perhaps 'rotating the clock frequencies' and voltages randomly within some narrow window while running another thread that takes a few percentages of each core and bounces around the core would fool this?
I think I may know how this is happening. There are several websites that offer subcontractor work to anyone intelligent enough to fill out an online form and lie about their experience and credentials. It used to be different, you had to prove you had skills, go through checks, etc. But nowadays, the sleazy companies posting the work to be done are paying SO lowly that the professionals are ignoring those jobs and the unskilled people are taking them. No checks, no requirements, nothing except that they're willing to work for under minimum wage.