The tracker takes away the Revive Deaths.

To elaborate, when you're revived. That death is taken off your KD Ratio as if it ever happened. Say if I killed 4 but died 4 times. But I got rezzed on those 4 times, then my KD ratio would be 4, not 0.

The tracker gets rid of those revives. To help show when you actually died, medic or no.