Some parts of the descriptions were a little different from what I've seen elsewhere. An example would be being fluent at B2, but not being able to watch a movie in the other language without difficulty at C1.
Well, the definition of fluency varies a lot from people to people, including linguists. But the strict definition of the term is "when language flows", it says nothing about grammatical mistakes. As long as the speaker isn't hesitant and is understood by natives, s/he's considered fluent by this definition.
Some parts of the descriptions were a little different from what I've seen elsewhere. An example would be being fluent at B2, but not being able to watch a movie in the other language without difficulty at C1.
Well, the definition of fluency varies a lot from people to people, including linguists. But the strict definition of the term is "when language flows", it says nothing about grammatical mistakes. As long as the speaker isn't hesitant and is understood by natives, s/he's considered fluent by this definition.
See this wikipedia article about language proficiency.