You shouldnt ever pull in the clutch unless your going ultra slow (like moving the bike into the garage or something). Someday (and it will happen) you will need power to straighten up the bike to avoid something. If you have to release the clutch it will cause a shock in the drivetrain and the back tire will most likely kick out from under you. Also a very bad idea to use the brakes while cornering. Front brakes while cornering can cause a tank slapper (when the handlebars smack back and forth all the way to the tank), and the rear can cause the back end to slide out. Some of the best advice I've heard is shift and brake early, meaning be at the right speed in the right gear going into the corner, so all you have to focus on is leaning and maintaining the speed you need.