Have you seen these stopmotion videos?
https://www.youtube.com/watch?v=z8uaHtesie8
how is this fluent animation even possible?
Frame blending is a major factor, as well as a a large number of keyframes coupled with a higher frame rate.
>>5422510
This. Plus motion blur helps and an understanding of natural movement physics. I'd consider myself pretty good at movement animation, but sprucing it up with effects like that is where I fall short.