I keep coming back to this topic because certain aspects of it relate to close experience in my electrical engineering career:
I have been on the side of having to investigate, determine root cause, and decide corrective action on features which are failing, or have the potential for failure, on products already in the field. It takes time to study, design and execute tests, and finally come to a conclusion—we’re talking months, while customers expect it to take hours. I have to choose to tell a very demanding [aerospace company] customer, “I don’t have an answer right now, I’m working on it”, and expect more questions and backlash. It’s just part of the job.
I see this as being no different for the engineer(s) tasked with looking into the power cable topic on the Quad Cortex. Is there a problem with pulling the power cable? What exactly happens to the QC if there is? Can the failure mode be replicated multiple times? How do we design a test to prove or disprove theories about this behavior? Even if just pulling the power cable or cutting power is not a problem for users now, could this cause damage to QC devices over time?
Yes, we were told in the past that we could free shut off the QC by unplugging the cable; now the manual tells us something different. It’s possible that there may have been previously unknown issues that arose by users unplugging that way, so maybe the company is suggesting to go through the power-down process out of an abundance of caution for everyone.
Do whatever you feel is safest and best for your QC.