they are head shy because their eyes, heat pits, sense of smell, and sense of vibration are all located there. also they need their head for such basic things as eating, breathing, and thinking. also its the most vulnerable part of their body.
you might as well ask whats wrong with male soccer players when they put their hands in front of their private parts when expecting a potential 50+ mp/h ball.
i would say if you stop buggering their heads and just handle them normally and dont stress them, chances are good that it might to a degree go away as they build more trust![]()