Root A was a whole clusterfuck. Made zero sense without reading the manga, it's "canon" in many parts but a whole ton of it doesn't make any sense.
They just ended it on the most "uh...ok, I guess it's over now" endings you'll ever see.
The parts that were canon were
-Skipped a lot of important details
-Weren't actually canon
Notice the last part. Even if they made the detail the same, its not the same. I don't wanna side-track with this because it'll just be me derailing a thread(again) but yeah, people think Kaneki joining Anteiku was canon. But then again, after reading these current chapters...