anyone actually optimizing youtube videos for seo successfully?

the title and the first line or two of the description do most of the work. put the phrase people actually search near the start of the title, but write the title for clicks, not for the keyword. honestly retention matters more than any of the metadata though. if people bail in the first 30 seconds no amount of tagging saves it, and tags barely count these days anyway. chapters help too, they can show up in google results as key moments.