Question: What documentary had music composed by the person who wrote "I'll Feel a Whole Lot Better"?
Sentence (from "Gene Clark"): Although he did not achieve commercial success as a solo artist, Clark was in the vanguard of popular music during much of his career, prefiguring developments in such disparate subgenres as psychedelic rock, baroque pop, newgrass, country rock, and alternative country.
Relevant evidence: No