VR 5.4.0f2: UnityEngine.VR.VRDevice.isPresent is inconsistent with OpenVR + Rift CV1

Reproduce the bug by setting OpenVR as the first choice in "Virtual Reality SDKs", and have Oculus CV1 connected to your computer.

Hide the headset from the view of the Oculus camera, so that SteamVR will display the "Not Ready" status and the following message (playing & stopping Unity editor is sometimes necessary):
"The headset is connected but not tracking"

These conditions produce below values:
UnityEngine.VR.VRDevice.isPresent == false // should be true
Valve.VR.OpenVR.IsHmdPresent() == true

If Vive is connected and has the same status in SteamVR, then both return true, as it should be.

I use the UnityEngine.VR.VRDevice.isPresent in applications to detect whether the HMD is connected to the computer, often in Awake() or Start() invocations that are called only once. If that variable returns false then I assume that a HMD is not connected to the computer, and set up my scene accordingly.

UnityEngine.VR.VRDevice.isPresent shouldn't return false if the HMD is connected and merely occluded from the view of the basestations/cameras.