I must be reading it wrong. Must use single hooks to me does not mean only one hook. It means no treble hooks. Side drifting and herring hook-ups would not be affected because where would someone side drift or troll herring where there is a NBLR in effect? Those areas are usually not very "boat-friendly". On the Chehalis it is single, barbless hooks only but you can use more than one hook on herring rigs or plugs.