The move itself is sorta like a cross between a flaka and spock. Sound ridiculous? My theory is that the entry is a lot like a flaka (deep downwind, unweighting everything) and if you do that correctly the exit will be like a spock (sail steering with some slight backwinding). The actual initiation of the move is different than either of those moves. You sheet in while jumping like the vulcan, but then you hold on and kick the tail as far downwind as possible.
When I watch this video the main mistakes I notice are:
1. Not enough speed off the wind. Like the flaka, a proper setup is a big key to success for the grubby.
2. Not getting the sail back across my body during the slide and extending the clew hand (often symptomatic of the sail being heavy because you don't have enough speed).
3. Leaning the mast too far downwind during initiation. This is the crash that tends to roll me into a quasi loop.
Anything that I'm missing?