Prior to CCP changing the number of drones a ship could control, this skill was completely different.
The skill used to read: 'skill at interfacing with drones. +1 drone controlled per level.' This would apply to all ships, but would be restrictive as to the size of the drone bay. It was not uncommon to see ships flying with as many drones as possible crammed into it.
Ships that specifially benefited from this were the Dominix,Vexor and Guardian-Vexor (possibly Arbitrator, I'm not sure). These ships had an additional +1 controlled per level in their abilities, bringing the total they could control up to 15. These were truly Drone Boats. The only ship to maintain the bonus is the Guardian-Vexor.
The Dominix and Vexor changed, to the 20% per level bonus when the skill was changed to the same. The reasons for the change were that the drones were causing too much lag. In theory the 20% per level from the skill, and to the ship, made up for the loss of drones. To this day many drone users, who were around then, still maintain that their fire power is reduced.
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