>>312121951
>>312122702
"Inside out" is supposed to mean "the sensors are located on the item being tracked, and they look outwards at something in the environment." Lighthouse tracking is indeed inside out, as both the headset and the controllers each have their own sensors on them, and the sensors look outwards at the lighthouses, which are just markers. 

As he pointed out, the Rift CV1 cameras were the only mainstream outside in system. With outside in, the sensors are out in the environment and looking inwards to detect signals coming from the headset and controllers.

>>312122886
Whether it requires external hardware is irrelevant. Besides, quest cameras do require external hardware to do tracking. They can just use any visible features as the hardware instead of requiring something specific. If you try to use the quest in a perfectly featureless void it'll fail.

>>312123631
It depends on what you're doing. Quick movements over your shoulder get general directionality but no precision. Archery and sniping with rifles have been known to have problems. Anything that involves holding your hands behind your back for more than a couple seconds is broken. It can be an issue for high level beat saber play: it won't happen a lot due to the nature of the game, and Carmack specifically optimized Quest 1 for Beat Saber, but it is possible to miss a block once in a while while doing wide swings. For other headsets, the exact arrangement of the cameras affects how bad it is. The htc cosmos is by far the worst, which is why everyone acts like it doesn't exist. Note that the cosmos elite uses lighthouses and only the basic cosmos has dogshit tracking.