I know this isn’t what you wanted to hear, but knowing the recommended methods will shine through in the final product. Almost every developer who has done Gear VR development will immediately notice things like the gaze cursor being a set distance from the head instead of it being projected on the surface you’re looking at like it should be.
Developers will appreciate the attention to detail and users will have no idea, but they won’t be sick and won’t have headaches or eyestrain. The last thing you want is a user to leave your experience with simulator sickness.
So let these documents guide your development process and if you decide to stray away from the path set before you by Oculus, make sure you understand why it’s not recommended to do it that way and try to minimize any negative effects.