That’s a tough one I haven’t really seen solved. I’m pretty sure you’re equating this multiple texts with timing thing to a bullet list plugin. The elusive bullet list plugin would be able to add timing where specific bullet points appeared and specifiable times. As yet, I don’t see a way to do that. You can control where the build in and build out happens, but everything in-between is stretchable by design, so specific, adjustable timing isn’t really there. You can do some things that I’ve tried like having adjustable delay start on behaviors but it will only get you so far and cause other issues.
BUT, assuming you don’t need to make a user friendly commercial product….
Make your text with evenly spaced timing of all the text elements that you’ll change in FCPX. In FCPX, change the texts, then compound the title in a compound clip. Now you can add hold frames and/or speed adjustments to the compound in FCPX to get the timing just right. And it really makes tweaking the timing easy. Just extend or shorten the hold frames, which generally you would apply after a text has animated on and come to a stop, and before the next text comes on or changes, etc.
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