it is delayed because the crystal we use that is why for higher research ppl generally you other clock source… exaclty i dont remember what is that term… “partially it is an atomic clock” which basically some of relation with the nuclear half life period i dont know its complete details…in the case of watch for more acuracy analog clock are prefered rather then the digital one… you yourself can see the difference.. buy a local digial clock and a standard one any branded digital clock… set them with same time just in few months you can notice the dealy b/w them.. that is why standard companies digital clock are more costaly than the local one… its a very nice concept i read a long back thanks for repolishing my old dead blocks… i will surly write an artical on it and send it to you as soon as possible…..