Hang on. FF is fictional superhero-style action. It's not meant to resemble anything realistic. Its mockery of physics is quite intentional.
Exactly. Lin made FF that way intentionally. The physics come from the Road Runner / Wile E Coyote school of science and they have always been up front about that. The question is more "Does Lin direct the movies well for what they are intended to be?" and that answer is yes.
Which brings us back to waiting on a screenwriter - that is the next big thing and where we REALLY need someone with some Science Fiction cred.