There was a 15 minute Dragon Warrior 1 speedrun that worked pretty much like this. Dude did it live and it was mostly reading off a sheet of paper with all the exact inputs. RNG in a lot of those older games for some reason could get their seed changed into something predictable and favorable with certain arbitrary controller inputs. Stuff like hitting down down down left right before selecting the Sleep spell would guarantee it worked on the final boss despite the usual 2% chance. He just blazed through the game by guaranteeing encounters with metal slimes and critical hits before they ran away.