both , just like surfing bonga, ride the wave down too far and the wave crashes upon you , but get yr timing right at the top of the wave and you surf the face of the wave all the way along the beach until it spits you out..they bet on the drop and the peak of sp and just like the old song says, Ya gotta know when to hold em and know when to fold em , know when to walk away and know when to run..
