Great eye. One of the things which would frustrate a truly obsessive "crawl-recreator" is that the original element has photographic warps in it as it travels. The warps are non-uniform and hard to detect but you can see them if you really look. For example, from the bottom edge of the frame to about a 1/3rd of the way up, the letterforms actually compress and stretch in height like a spring a couple of times. There are also horizontal pinches and stretches which happen over the animation. This is why, to preserve the original crawl, I have to register my frames to the originals. The way I even detected this in the first place was because I was tracking a single frame of the letterforms on top of the original ones, and where mine were perfectly proportioned, I could easily see the ones below stretching and pulling and shrinking, etc. Now, remember I'm not talking about them moving around in space or jittering; I'm talking about the actual dimensions and proportions of the original letters changing frame-by-frame over the animation. So if you were just going to do a crawl recreation, you'd lose all that, especially near the end of the sequence, where the letterforms exhibit a lot of these sorts of quirks and they're different each frame. If I get a chance, I'll stabilize/lock one of the lines of text in place, so you can see all the warping stuff that happens to it over its run.