Yes, that kind of the idea of it. I thought I gave enough motivation in the readme file, but apparently there’s room for improvement 
Let’s assume you’ve taken a (very short) timelapse consisting of 10 frames. If you’d take your pictures as they were using an automatic algorithm (e.g. your cameras jpeg routine) you might notice that brightness and color flicker. This does not happen always and depends heavily on how well your camera’s light meter and white balance algorithm works but it happens.
Back to your frames. You start working on your first frame in darktable and once you’ve got a result you’re happy with you just copy the entire history stack over to your other pictures.
But no, what happened? The highlights are blown out and the colors look totally off, even stronger for every picture. The lighting conditions changed rapidly during your shot and your edit of the first frame doesn’t fit your last frame. How can you fix that without tediously working on every single frame?
It actually pretty easy. You just declare frames 1,4,7 and 10 as keyframes, do your editing there and interpolate the module parameters for 2,3,5,6,8 and 9. So, instead of editing 10 frames, you’re now down to 4.
I hope this clarifies things a bit. If not, feel free to ask again 
Looking forward to hear back and see the results!