This is a natural process that birds will do, its a way the male will feed the hen and even help feed its chicks, young male birds will practice regurgitating often and will be preparing to look for a female, part of the grooming process is to feed the female and show her that he can provide for her and her chicks. My hen kakarikis laid seven or eight eggs each time they laid so its a lot of mouths to feed, your bird is most likely eating for it self and then taking extra foods that it will partly digest to regurgitate. I will say if its regurgitating about a tea spoon in one go that is about twice of what mine had done at one time. although mine did regurgitate often leaving small piles of processed food in different places. I agree get him checked, you either have a extremely healthy bird that is full of passion (what I expect) or it may need some antibacterial treatment. I will say he looks stunning, How I miss the males calls.