My POI does not change with shooting position in any of my rifles. Change in POI with position change is most often caused by a change in eye position and exasperated by parallax not being set right. People are taught to set up rifles for prone shooting and this usually results in the cheek riser being too high for positional shooting. You get shadowing at the top of the view due to the eye being higher and this results in the bullet hitting low. If the eye changes position horizontally, there will also be a shift in POI in the opposite direction. Jacob demonstrates it really well in the video.
Having to incorporate offsets would be a nightmare in matches like PRS where positions and target distances are always different. The only offset I record is for urban prone.