Sorry you missed it, there was a long thread on this just before the "CRASH". Will try to keep it simple.
Degreeing a cam is to make sure it it is installed at the designed position.
Then there is degreeing a cam to a position different than design position for performance.
Basically what happens is the cam's HP and torque characteristics are move up or down the RPM "scale". It changes nothing about the cam it self as ground, but there can be some power increase or advantage if cam characteristic are moved to a point where more effective.
Advancing the cam moves events down scale to a lower rpm, making it happen earlier in relation to the designed cam position
Retarding moves up "scale" to a higher rpm, making it happen later.
Degreeing a cam to a position other than design is a mostly race tuning tool to help match HP/ torque to gears or intake /header efficiency. For street it help put the torque at the best RPM range for gears used.