Conversation so far:
What was special about the grateful dead?
The Dead's early sets centered around blues and R&B covers chosen by McKernan.
By the end of 1966.
what happened in 1966?
the end of 1966, Garcia had improved his musical skills and wanted to assert himself more as a leader and musical director.
leader of what?
and musical director, changing the band's direction and reducing McKernan's contributions.

Question: how did he change the direction?
Self-contained rewrite: how did Garcia change the direction?