That's an interesting theory, though it doesn't match my experience. My cat tends to bring the mouse inside through the flap, holding it in his mouth, and then will repeatedly grab it in his mouth, move somewhere else and let it out again. He has the option of killing it just by biting down at any moment.
My own hypothesis is that cats catch prey and play with them for a while as a way of getting more training per kill. They probably find some enjoyment in it, which is likely evolved as an incentive to practice. Cats are certainly well known for their playfulness, which tends to be stronger at a young age.
I suppose both theories might be true at different times, depending on the context or the prey. I guess mice aren't particularly capable of doing any real harm to a cat.
My own hypothesis is that cats catch prey and play with them for a while as a way of getting more training per kill. They probably find some enjoyment in it, which is likely evolved as an incentive to practice. Cats are certainly well known for their playfulness, which tends to be stronger at a young age.
I suppose both theories might be true at different times, depending on the context or the prey. I guess mice aren't particularly capable of doing any real harm to a cat.