Yes that method seems to work, until you look at the volume that gets through, and that shows it does not work, so something more drastic has to happen. The CG only has so many copters in a given operations area, there are only a few CG that can shoot that well in the same operations area.
The lone copter will need to refuel after a certain time; the go-fast can hide on one of the many islands and coves - where the drugs can be unloaded. Night operations are even more difficult, especially in fog and heavy weather where copters cannot safely fly. Go-fast boats have successfully gotten away from the CG.
Deadly force is the only thing that can interdict the majority, if not all the go-fast boats. Unless you imagine foreign drug runners should have US citizen rights granted and due process given, before any action is taken which might harm a hair on their stinky heads.
