Why Americans Don't Like Jazz

[Bill McCloskey]

Speaking of Duke, would he have achieved his musical success without Billy Strayhorn?

The quick answer is Duke already achieved musical success long before he met Billy Strayhorn.

[Andy Greatrix]

I think I read somewhere that bebop came about at jam sessions where less advanced musicians, who hadn’t done their homework, would sit in, not play very well and take several choruses to prove it.

The more advanced musicians would write songs laced with two five one changes and altered chords to scare off the hackers (like me).
However, as the more skilled musicians started to play these tunes, they realized that they were on to something special and it just morphed into bebop.

[Andy Greatrix]

Bill, you are absolutely right.
Duke was successful before Billy Strayhorn, but even more so, after Billy joined the group.