Originally Posted by
ScottCommutes
Right on. If it ain't broke, don't fix it.
However, the danger is that the brakes might become spongy so gradually that while your perception is that they are still great, the reality is that enough air has entered the system to affect performance.
My take is that if you are the kind of rider who barrels down mountains like you are immortal, then you better know the manufacture's recommendations for service, and either be a darn good mechanic yourself or have one on standby. The way I ride, I could likely stop with my foot even if they failed, which they likely won't, just all at once.