The Animation/Motion Clip is a system where you can store all your animation that is expressible in keyframes, into a clip. This clip can be understood like a film clip. Based on that you edit you complete animation of a project then like you would edit a movie, think of cuts and blends. The name for that is Non-Linear-Animation.
This is particular interesting not only for character-animationwork, it is especially useful for team work. This team work idea will be discussed this summer here on Cineversity.
Yes, this might help to make things loop able if the file is well prepared for this.
Thanks for your suggestion and I hope you will benefit from the upcoming series.
All the best