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).
Did it reach bill board charts?
).
It reached number twenty-four in the US.
Did they still go on tour?
CANNOTANSWER.

Question: What was The Mamas & the Papas Deliver?
Self-contained rewrite: What was The Mamas & the Papas Deliver?