It works if you have the means to fix the exact coordinates of the enemy batteries, some of which are probably self-propelled and can be rapidly repositioned. Then you need weapons that can reach the target and destroy it. I'm just guessing but it seems they could try infiltrating Ghadaffi’s line at night with small teams of saboteurs to kill the gun crews and destroy the artillery and launchers.
Infiltrating Qs lines at night with small teams of saboteurs requires those small teams of saboteurs to be both armed and trained on how to use explosives and supplied with them. Doubt there were many in Misrate with either. Perhaps this is what the British have in mind. It would make sense.