Tatenashi is literally the only thing stopping this season from becoming garbage. ._. It's as though this season is a gigantic "screw you" sign from the fanbase and TBS to Yumizuru for not giving a damn about IS at all. Mutilating half of the given LN content (yeah Vol6 didn't exist at all and Vol8 had literally only the opening and ending used) and dumping in anime-original content seems like an excellent solution LOL
I'm not surprised that the production staff had to do something like this though. V7 would've been perfect as a place to round everything up, but then you wouldn't have enough content for an anime. Adding just V8 would've been weird though...
honestly, i'm actually looking forward to the finale, because the more i watch this, the more my mind is going "wow this is just a gigantic middle finger pointing at yumizuru's face"