Yes, it sounds reasonable! Once a pup realizes that holding out will make you give in, you start the cycle you are now in with him. The longest you have gone is 1.5 days...you probably will have to go 2 - 3 to win....but you will win!
He just needs to know he is not getting a replacement if he doesn't eat.
BTW, I have done this and never had a pup go so long that he was hypoglycemic. It is rare for a healthy pup to do that.