Conversation so far:
When did Rodgers and Hammerstein start developing Oklahoma?
Rodgers and Hammerstein started developing Oklahoma! in 1941.
How were the reviews at the New Haven tryout for Oklahoma?
The New Haven and Boston audiences were enthusiastic, although the reviews were only fair for Oklahoma.

Question: What changes were made based on the reviews.
Self-contained rewrite: What changes were made based in Oklahoma! on the reviews?