This video outlines the nature of auto-armor, it is not as simple as most people think. Most veteran players simply think auto-armor enables amor-mode once you begin to take damage, in this video it explores how auto-armor really works.

http://www.youtube.com/watch?v=N5SVJdw3T94

Video imbed added

lol ur a little late to the party

lol ur a little late to the party
And yet still most people don't seem to know this.