I think this was my reasoning. Also, I believe the way it is worded, the resolving their shots makes me think of order, like weapons, etc. - if they had wanted it to function like the first, it should have said that the units function as a single unit for all purposes during this attack or some such. Granted, GW writing etc., but still seems like they would have chosen more specific wording if they meant abilities to confer. From my understanding, markerlights are something on the target unit right? So it makes sense those apply for the full attack, but not the other stuff.
This is exactly my thoughts. They call out markerlights, why do that instead of saying any special abilities.
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