The enchanting building can indeed disenchant epic items but most likely you will get fragments of temporal crystal instead of a full crystal. Enchanters can turn fragments into a full crystal with their daily cd so having the building allowing you getting free crystals would pretty much neuter the profession completely.
except for the fact that an enchanter gets WAY more (3 times more+) materials out of disenchanting,
so if your mainchar is going to raid, it should be enchanter for the free gold/enchants you provide yourself.