As a casual follower of speed running / high score community and HN frequenter, I'd say everyone who doesn't follow would be surprised how much detail goes into mastering some of these old games. These guys decipher everything, and find tricks that depend on "subpixel" perfect timing to shave off mere milliseconds. And they have thousands and thousands of attempts. The community at large thinks Billy Mitchell is a piece of shit, so tells me enough. Here's some channels if you want to learn more.
https://www.youtube.com/user/RWhiteGoose
https://www.youtube.com/channel/UC3ltptWa0xfrDweghW94Acg