This would make absolutely no sense though.
No reason to mess with a successful formula on Thursday to try to take viewers away from another network on Wednesday. Especially when Blackish is only 30 minutes.
You don't need the highest/best rated show to be deemed a success. I'm sure Black-ish is doing well enough being that they ordered more episodes. Their lead in (Modern Family) does not have the same demographic as Blackish and always does numbers. All they want Blackish to do is keep some of that steam to not have a complete tune out after MF goes off. Which makes sense, since if you were going to watch Empire, you wouldn't be watching MF and tuning in 30 minutes late. Not to mention Empire seems to have lost a little steam from last season.
The show is doing well lol I don't understand why there's even the need for this back and forth. It maintains its lead in for the most part from modern family so it's keeping the demographics and more than likely getting a season 3. Of all the shows abc had tried in that spot they finally got something that works. Although happy endings still did better than anything in that spot but for some reason they felt the need to fukk with it and make me sad