[Suicide Junkie]

1) If you're finishing off hulks, you don't have to worry about multiplexing them, since you can easily get a 20:1 kill ratio

2) PD dosen't count towards the limit when autofiring on fighters as they move. It only counts against multiplexing when manually firing them, which usually only occurs against sats, which stack.

3) PD autofires on drones, IIRC, and so, dosen't use multiplexing.

4) Ion/Tachyon/Neutrino/Nullspace weapons, combined with a 10% damage per ship rule would require a good multiplexing. That's a fairly specialized ship example, though.