Thanks for the post - I put together the tool above. I tried to strike a balance between being concise but also capturing all the important details. For that reason, the tool is hit or miss on longer (> 45 min) videos - the summary on this video is good but I've seen it omit important details on other long videos. The tool also captures relevant screenshots for each section.
Hopefully it's helpful. You can summarize additional videos by submitting a youtube URL in the nav bar or the home page. Also, feedback welcome!