Sentence:  The upheaval in the creative unions seems to have gone further than expected and the forces for renewal took the <WSD>bit between their teeth</WSD> — to such an extent that the writers' congress in June of the same year would follow more staid formulas and attempt more of a compromise between the old and the new, as compared to the Fifth Congress of the Filmmakers' Union in May, where the old guard of film directors had been eliminated (Lev Kulidshanov, Vladimir Naumov, and Sergei Bondarchuk). 
Meaning of the word marked with <WSD> tags:  A large degree of focus and commitment to a task.