The hydraulic control circuits upgrade has a mod that says "Defender chooses ship component affected by Ion weapon quality as opposed to the attacker." What is this referring to? All the Ion weapon quality and the Ion entry in the starship section say is that ion weapons do system strain damage.

The first paragraph under Critical Hits on page 243 mentions, "Ion cannon blasts can short out systems." I guess if the attacker is aiming for a specific system component, say to shut down shields for the next round, the defender gets to say that their sensors are knocked offline instead.