Auto Tune?

[rg]

http://www.gearwire.com/media/moog-litt ... -wnamm.wmv

How's the auto tune work? In the Gearwire demo Cyril Lance says you tune it then u can put on auto tune after. Does that mean you need to tune it manually then turn on auto tune afterwards to keep it in tune? Can you not just turn on auto tune and it will tune the synth by itself? Do you need to retune it and put on auto tune everytime you turn the synth on?