One on the clutch, one on the front brake at all times. its something I learned in dirt.. It helps me to 'point' the bike where i want it to go, lets me have better throttle control, easier.... just personal preference.
Not everyone likes it, and thats OK... I'm pretty sure a guy whos covering the brake will start braking before the guy who isn't covering.. just seems like common sense.
'If you wanna play tough, you better be stupid!'