Comment 4 for bug 1343411

ScislaC : if that you said is true, and multipage spec does not allow elements with the same id on different pages, it doesn't change the need to implement multipages in Inkscape. We still need multipage support for onion-layered frames. The only difference is that at the end inkscape would save the pages as individual svg files.
Then the snap.svg library will take care of load all svg as frames and tweening the various states of the objects with the same id in all svg frames.
That is not the difficult part. The difficult part is to be able to work on various versions of the same object to animate it. If I want to create a simple flag animated by the wind, I need to create some frames in Inkscape moving the single nodes of the shape frame by frame. With the snap.svg interpolation, I need fewer frames, just 4 keyframes for example, but I still need to compare the various frames while progressively changing the nodes positions. This means that I need the option to have the same objects in different inkscape pages, assigned to an index that will correspond to 1/30th or 1/60th of a second of animation. If I create a 2 frame animation, using page 1 and page 10, the entire animation loop would last 1/3th of a second on a 30fps scale, and 1/6th second on a 60th scale. If I want a slower animation all I need to do is to move the end svg frame from page 10 to page 30 (or to page 60). This is what I did in Flash editor for years, and it works perfectly. It works because it is simple and intuitive. Please add this feature to Inkscape. Even in its basic form, it would be incredibly useful for making svg animations.