Since none of it is documented by Tesla, it may be a secret handshake.
Then again, some have suggested in various threads that the additional brake hold-down and "wait for the T" enables some sort of more robust reboot. IDK that for a fact, and have never seen more than supposition here on TMC regarding it that I believe to be credible. When I queried the Tesla 800# about it, they said the sequence they suggested was important. Since it happened shortly after I took delivery, and it worked better than the simpler "hold both buttons until reboot" I had found in TMC threads and tried multiple times without success, I was too much of a noobie to ask more questions. Now, that more complete process is what I generally follow if I'm parked even though my perception is it takes a few more moments to accomplish. Only when I need to reboot while driving -- generally because of an Infotainment oddity --
Oh Hum -- do I use the short-hand on-the-fly reboot process. (I could draw analogies how I occasionally used one of a couple different IPL sequences that took different amounts of time and did slightly different things reloading/refreshing parts of firmware before reloading the OS in my IBM mainframe days, but hey, that would date me way too much and most of the young 'uns reading this wouldn't care what I was talking about anyway.
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