Q: MacBook Pro always hibernates

Yep, I get what was wrong, thanks for restating.

Just to be sure I am clear on your reasoning: Because it does not hibernate on battery anyway, might as well turn off the setting for power too, and the result is to fix it for power (no more hibernating while plugged in), and has "no effect" on battery because it was broken anyway? I suspect if they offer a fix (wait, Apple has not admited to the problem, so that may be a while), we would want to set this system variable back to 1?

Cheers

Alternatively, to be a bit more future-proof, you can do this:

sudo pmset -a autopoweroffdelay 86400

Instead of disabling autopoweroff, this will change it from 4 hours (the default 14400 minutes) to 24 hours, so it will only hibernate after 24 hours.

As far as I can tell, the plan seems to be to auto-hibernate after being asleep for some time, to prevent battery drain. (I actually applaud this, because it ***** when my MacBook's battery is completely drained after sitting around for 3 or 4 days.)

However, they seem to have introduced a bug where it hibernates when plugged in, and doesn't hibernate when on battery, which is pretty much the exact opposite of what you want. Almost certainly their code just has a sign flip somewhere.

I'm pretty sure this was introduced with a system update at some point, so presumably Apple will fix it eventually. When they do, they might not reset any pmset fiddling you may have done.

This is why I recommend lengthening the autopoweroffdelay from 4 to 24 hours instead of turning it off altogether. That way, when they do eventually fix it, you'll still get the benefit of auto-hibernation after a more reasonable 24 hour span, and have a working laptop even if you don't touch it for a few days.

Btw, here's a much longer thread about the same issue:

https://discussions.apple.com/thread/4512384

Yes, you both pretty much get it now.

Apple has posted an official response to this!

http://support.apple.com/en-us/HT1757

Apparently, the reason auto power off happens when plugged in is due to European energy standards compliance. So the logic isn't backwards after all. It's just that its goal is to prevent long term power grid usage, not improving user experience.