Sorry for the late reply, I'm quite busy lately. So basically the game ticks 60 times per second, and it isn't designed to handle extremely fast machines. When a machine should craft a recipe more than once per tick, it would only produce the result once, which would cap the recipe at 60 times per second, and if the recipe has productivity bonus smaller than 100%, it would produce more products than it should, and for higher than 100% productivity it would be less.