However, it also allows you to re-sync a device just by putting in the current datetime - at the cost that it'll drift at a rate of up to two seconds per year (

However, it also allows you to re-sync a device just by putting in the current datetime - at the cost that it'll drift at a rate of up to two seconds per year (though the current average is more like 0.5s given 27 leap seconds in 50 years).