Originally Posted by gharper
The surface area of a well used anode is considerably less than a new one and will be at end of life at a faster rate. If you have a well used anode at the beginning of the season you need to keep an eye on it during the season or may have no functioning anode by the middle/end of the season. A well used anode is more fragile and can break pieces off into the tank particularly when bouncing along on the road.
I think along those lines also . The cost of a new anode is sure a lot cheaper then a new water heater . When you remove it , you also would get to clean it out , which should also let water heater work it's best and extend it's life . Pat