Conversation so far:
What happened in 1967?
The strain on the group was apparent when they performed indifferently at the first Monterey International Pop Festival in June 1967.
What was the issue?
The band was badly under-rehearsed .
Did they start to practice more together after that?
They rallied for their performance before 18,000 people at the Hollywood Bowl in August (with Jimi Hendrix as the opener).

Question: Did it reach bill board charts?
Self-contained rewrite: Did The Mamas & the Papas performance reach bill board charts?