Well, I'm sorry I ever got into this discussion. If you never did anything similarly silly early on in your career, then you're a better man than I am.
I don't recall whether the numbers were upside down like 60/80. I just remember once or twice reading the numbers off the machine only to immediately realize that they couldn't possibly be true. And that is how I learned not to trust the machine.
The lessons learned from our mistakes. It only took me one time to forget to switch the nasal cannula from the ambulance tank to the portable when unloading a sweet 85 y/o grandmotherly patient. That was probably the worst cussin' out I have still to this day taken from a patient and it was well deserved.