“Boredom is the feeling that everything is a waste of time; serenity, that nothing is.” – Thomas S. Szasz

With our home refiner (the Santha Melanger) it is pretty difficult to over refine. But it can happen. If you chocolate starts to really thicken up, and you have been refining over 20 hours or so, you may be starting to overrefine. If the flavor is still not smooth as you want, remove the tension spring, and effectively you will be conching but not refining.