Some say it’s pointless
But here’s why I think it’s pretty much necessary
It’s perfect source material for building jazz language. You can rip bits of people solos, learn them in the right context and use them when you solo.
You can really get into the rhythm, swing and small intricacies that make up someone’s style and the greater style that is jazz music.
You can get the feeling of playing a GREAT solo. When we first start playing jazz, chances are that we aren’t playing GREAT solos.
We are just learning right now. By learning to play someone else’s genius improvisation we are getting the chance to play great music, as we do when we learn to play classical or folk music, we play GREAT pieces of work by master composers.
Anyone disagree with me? I'm ready to have my mind changed, I promise!