I'm not sure if this is something new Apple is doing or something wrong with my machine. A few years ago Apple started including Apple Hardware test on machines in addition to providing it on the restore DVDs. You accessed it by holding down "D" while booting. On my Macbook Pro retina 15" holding down "D" starts a internet-based version of this test rather than a local one. This used to be accessed by holding down "option-D", unless a local version wasn't present. So did Apple stop including the local version, or did it somehow get erased/corrupted/whatever? I don't really need it at the moment, but it caught me off guard. And if it is missing, is there a way to get it back. Internet connections aren't always around.
And since I'm sure someone will ask: I definitely have a bootable Recovery HD partition.
And since I'm sure someone will ask: I definitely have a bootable Recovery HD partition.