He basically trolled the people who kept insisting that she was Karin's daughter. For a few weeks many of them got super exited thinking they are going to get their wish.
that's right as well, he trolled the ones who believed that and played with the idea,
But he trolled SS much more. I doubt anyone with their brain in the right place think the gaiden was positive to sakura and sasusaku in any way. Besides all the shit, SS had a slight possiblity to look at least ok if portrayed nicely, but any potential positive development for sakura and the couple was killed and put in the trash.