True, it comes down to piece of mind. Inspect the pulley, if its loose at all (rocks on the shaft) replace it. some pulleys have a sealed bearing in them and you cant really lube them. If you can its most likely because its wore out enough that the bearing is no longer "sealed" an you would be living on borrowed time. On the other hand ,I've only ever had one fail on me and got lucky that it only shreaded the belt when it did, but the new tensioner assy. was over $200 (rare oldsmobile dealer only part)