Can someone explain why PD weapons and cloaking devices sometimes work on fighters?

I have carried ships that have these devices sometimes work, sometimes don't work.
Without changing anything in two different plugs, I can sell, then re-buy the same fighters and a different amount will work/not work.

(SkillVar is 0, if that would have any effect.)

Off the top of my mind, could it have something to do with the inherent gov (which also has a SkillVar, if I am not mistaken), as this seems to be the only thing that differs (the way you describe it).

Or maybe the game randomly selects an outfit-usage-behavior for AI ships, although I'd find that a rather Bad Thing and I guess we'd have found out before.

You need to check the AI attributes in the Ship resources that define when the ship will and will not cloak. Those control AI ship cloaking even if the ship does not have a cloaking device.

As for PD, make sure the "can be hit by PD" flag is set in the ship resource.

I assume when he said "re-buy the same fighter" he didn't mean "re-buy after I changed the fighter's AI attributes in the plug". And I also assume that he meant that PD weapons dont fire when mounted on the fighter, although, as I said before, when he used the same ship, it wouldn't matter wether it doesn't fire FROM or AT the fighter, since it should behave exactly the same in every case.

bman is correct, this is for this is for the exact same ship firing at the exact same target

For instance, say I have 4 fighters that can cloak. (same ship resource)
1 or 2 of them might not be able to cloak.
Then I land, or re-launch them - can't remember which, and then a different number will not cloak.

The same happens with PD weapons.

So, not only are the same ship type not acting consistant, but they are not even consistant about being inconsistant.

Also, there is no inherent govt associated with the fighters right now.