I find this thread interesting. I don't have a VR device, but I have a Tobii 4C eye tracker in use. Since a few weeks, I have to switch off the Tobii software (and thus not use the eye tracker), else I run into performance issues. Up to now, I thought this to be a Tobii problem (I updated the Tobii software recently, too) and have a ticket open there.
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But if VR users also have performance issues, which read similarily (for me ED itself also only uses about 50% CPU, the rest is used up by the Tobii software), I wonder if there might be something whacky going on with the interface. As far as I understand, Tobii and Oculus use the same interface to provide info for the head/camera position. Unfortunately I don't know much about that interface, but it'd be interesting if somebody who knows more could say if some whacky stuff could happen there, which results in performance issues? (E.g., as a wild guess: the game could request data updates at an insanely high rate, forcing the software to recalculate and update their tracking position all of the time and thus clog up the CPU. )
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Anyway, I can also be far off. It requires somebody with more understanding on the topic, to say if my issue is related or a pure coincidence.
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