Taika Waititi says 80% of the lines in Thor: Ragnarok are improvised, and while it seems highly unlikely Marvel would allow a director to take that kind of creative freedom (see Edgar Wright) he's the director. Waititi spoke to MTV and said this:
"My style of working is I'll often be behind the camera, or right next to the camera yelling words at people, like, 'Say this, say this! Say it this way! I'll straight-up give Anthony Hopkins a line reading. I don't care."
Like I mentioned it seems like Marvel would have a problem with that and Mark Ruffalo seemed to agree as Waititi adds this line confirming my suspicions:
"Mark Ruffalo would be finished shooting for the day,and he'd come up to me and he'd be like, 'Why have we not been fired yet? We are doing the most insane stuff in this film, so where's the phone call?'"
Apparently, that phone call never came and it's a good thing too because the latest footage from this film looks flat out incredible! For the first time since he started, I'm amped up for a Thor film, and that really tells me all I need to know. Can't wait to see it November 3rd. For more Waititi hit the video below.