What I meant was this: when using information warfare disabling everything would be more useful at some point: you attack with many troops and the enemy has a high rating. For example attacking with 4k vs 8k (after farm disable) troops, ratings like 20:15. With 500 to 1000 extra troops you probably still wont win. With 1000 defectors the effective troop numbers would be 10 vs 10.5. Before disabling the farm with 3k changing to you it would be 7*2=14 vs 12*1.5=16, so there would be fewer enemies left with disabling all. But the planet would still not be yours, so you either have to wait for an extra transport or use a destructive invasion tactic. You wouldn't disable the morale then of course.

Short version: there is a point where disabling both farm and morale gets you more. But it doesn't matter because information warfare is too weak at that point.