Using a bigger fork makes you eat less food, as weird as that sounds. It's not that your wrist will be too tired to keep shoveling stuff into your mouth; it's that you'll simply feel full with less food than if you were eating with a regular-sized fork.
In one study, researchers invaded a restaurant over several days and gave random customers different types of forks. Half of the customers were given forks 20 percent larger than average size, while the other half were given forks 20 percent smaller. The researchers went through the diners' plates when they were done and measured how much food was eaten off of each of them, which isn't creepy at all.
Why go to a restaurant to look at a stranger's food when you could just join Instagram?
What they found out was that the people who were given larger forks left significantly more food on their plates than those with smaller forks. But why would larger bites make you eat less? Because sight plays a huge role in our eating habits. We rely on visual cues to guide us when we're eating (i.e., how much food we see on the plate), since it takes our nervous system a while to realize whether we're really full or not.
So, if your senses are telling your brain that you should be satisfied, the brain will decide that, what the hell, you might as well be. When you use a bigger fork, you'll see yourself making bigger dents in the overall food on the plate, fooling your brain into believing that you're overeating. With a smaller fork, the transition from "a lot of food" to "hardly any food at all" is more subtle, so you keep on snacking well past the point your thunder thighs would appreciate.
Next thing you know, your dining room has no furniture.