Duplicate of https://forums.factorio.com/viewtopic.php?f=58&t=120100

Additionally in order to get to this stage you must have spent hundreds of thousands of resources to research those levels of productivity which means you’d need to do this for hours and hours before you got into any kind of net ...

This bug allows you to farm high quality parts such as legendary parts for free. Potentially very exploitative and game breaking.

When using an EM plant, or Cryo plant or anything else that gives a lot of productivity. I was able to cancel the recipe when the productivity gives you a free bonus ...