atnuts

ok, I'm not using my handbrake setup yet but some of my buddies are and when they're doing SS circles the bike sometimes gets away from them and rolls off and sometimes the drops are nasty. I'm used to covering the clutch and that has saved my @ss many times but I won't be covering the clutch when I'm on the HB. How do you guys stop the bike from rolling away when working the HB and you can't get to the clutch in time?