With the current system, I could release my song and allow people to make copies of it, even play it unmodified for free, but retain all my rights to modification. Then if someone wants to make a cover of it or a remix they have to get permission, as with standard copyright law. If LR had chosen the OAL I see only negatives from his perspective. But I definitely would want to retain artistic control over future changes. I never read through the whole thing, but the basic concept is that Jazz is based on improvisation of existing works.
Musical quotation is an ancient tradition.
Sharing enriches the musical repetoire.