OK, you all I am obviously not getting my point across clearly. These tricks can be taught to all fish (at least bigger than a betta). You only treat the betta with very small pieces of bloodworm, and you don't train them all day. In five minutes, you could probably coax your betta to do the "jump through a hoop" trick once, so that's one tiny piece of bloodworm. AND I said that you only do so much training until your bettas stomach is full. You CAN tell when it is full by the size of the belly, therefore, you will know when to stop.
I see what you all are talking about and that was a fault by me when typing. I train with multiple fish in one setting. I only do about 5 training sessions amongst all of the bettas in one day. I only usually do max 2 sessions per fish, and I don't even do that many once the fish get the trick down.
I would never put my fish in danger, and I am not overfeeding, this depends on the number of fish you have as to how many training sessions you do per day. My fish have never become bloated because I limit the amount of training sessions per day.
You know you have a problem when you would rather hang out with a Betta than some of your relatives...
If you like my advice, or have a question about your betta(s), please message me or comment on my page!