Is using the save function to "go back in time" generally considered reasonable for a speed run? That is, can I: Save, Discover a problem, restore to my save and then do it the correct way?

Sorry if I missed a link somewhere, but is there a page with the general "rules" or should I figure them out from reading the forums? :)

Hey welcome,

this depends on the category you want to run. In 100% all reloads are forbidden (stated in the category rules), because you can abuse it to increase the global green circuit counter. However in Any% you are free to reload at any time. Just notice that the time is taken in real-time, NOT ingame-time. So any reloads will usually be unfavorable. Feel free to join the Factorio Speedrunner Discord if you have any further questions: https://discord.gg/EakEWTf