Hi Itchy
Friction multiplier zero will trun off friction for that particular load case not the entire system. Same load case you can make with friction without friction , just your load case will increase.
1) W+P1+T1 Friction multiplier one
2) W+P1+T1 Friction multiplier Zero
You can make combination as you like just by incresing number of load case.
Regards
Habib