Someone who is on top of his game.
Did you see that kid dance, yo he's doin it.
The act of holding ones arm up at the chest at a horizontal 90 degree angle, and proceeding to move the arm from left to right, closed fisted, in a fast motion. Normally performed with the eyes tightly shut, teeth clenched in a wide opened mouthed manner and head swiftly moving from left to right in opposite sync of ones arm.
This is normally only performed under extreme intoxication (tri or even quad fade) and is often associated with listening to heavy-metal music, although it may be performed at any time, you'll just look totally ridiculous while doing it sober.
1) DAMN! Did you see Nick last night? After those 19 beers, 7 blunts and 12 lines of coke that fool was straight doin it!!
2) He's doin it!