biassocs: fix docs for set-at-once.
biassocs: fix docs for set-at-once.

AlexIljin/factor,mrjbq7/factor,mrjbq7/factor,mrjbq7/factor,tgunr/factor,AlexIljin/factor,factor/factor,bpollack/factor,AlexIljin/factor,factor/factor,mrjbq7/factor,bpollack/factor,factor/factor,AlexIljin/factor,bpollack/factor,bpollack/factor,tgunr/factor,factor/factor,factor/factor,tgunr/factor,tgunr/factor,tgunr/factor,bpollack/factor,factor/factor,tgunr/factor,bpollack/factor,AlexIljin/factor,mrjbq7/factor,bpollack/factor,AlexIljin/factor,mrjbq7/factor,AlexIljin/factor