I have a couple of coins that are in MS condition. There are also some die cracks running in the date and elsewhere. As a general rule, do these cracks lower the grade? Do they enhance the value? Do they decrease the value? Are they mostly for "specialty" collectors? Should I expect to pay less for the coin?
From a purely technical standpoint - no die cracks do not lower the grade of a coin. But they can affect the eye appeal which could keep the grade from being as high as it might otherwise. As far as value goes - it depends primarily on the coin. Some variety collectors are really attracted to die cracks - others want nothing to do with them. So as with anything else pertaining to coins - it depends on the collector. Some will pay more - some will pay less.