My recent frigate run would... butcher doesn't express the speed and ease well enough, it'll have to do. The frigates would butcher a single pirate stack in about 60 seconds, no losses no damage. If I could have just 1v1 them even 6 fleets they'd melt.
What frigates are you using? High-tech ones would have 40% in the fourth battle. 20% in fifth. Most others would have 70%, but they are also weaker, perhaps too weak to warrant using them.
Quite a damper on chain battling, isn't it?
This is why I don't think it's such a huge issue. You either run into the mob and have to fight them one after another, or you don't get the skill, bait fleets out one by one and get some rest between fights.***, you can just repair your ships with a SP and circumvent the whole issue. Scaling SP costs would help, but that would be its own thread...
I'm less against it now thinking about the limited number of cases, however, point well taken. Please do consider the AI may also have this skill. Can't join allies in the fight, enemy fleet has X skill. Pirate fleet has it and your merchants can't get helped by the patrols now.
There's a precedent for NPC fleets never using skills that player has access to: navigation, sensors. Some others are heavily restricted, such as Wolfpack Tactics (only small ship mercenary bounties from contacts) or Derelict Contingent (only expdrone bounties from contacts).
It would be nice to have the skill work somehow for AI nevertheless, though. Perhaps NPCs with this skill would have their battles end faster in the campaign map. It makes it obvious why you can't support a friendly fleet: it just died. However, this solution would also make the skill inconsistent, since the player could still support friendly fleets in some specific situations, unless those battles were literally instant.