Yes, that is a utility feature. If the brightness of your LED has substantially dimmed we will replace it under warranty. I say substantial because is it difficult to test for this. But if you go to use your Arc-LSH and it is much dimmer than you last remember it, we will test it to verify that it outside the range for that model. The LSx series had a normal variation from unit to unit (within the same model) of about 50%. The Arc4 improves on this consistancy (about +-10%) and the improved thermal management also increases the lumen maintenance.
Peter