I thought I would put this to the test with a bebop tune from Charlie Parker. Charlie Parker was nicknamed the "Yardbird". There are apparently two stories about this. One is that he lived free as a bird. The other that he was in a car that accidentally hit and killed a chicken (yardbird). Charlie Parker made the car stop so he could take the chicken home and cook it. Whatever. The name stuck and sounds quite cool. He must have liked the name too as one of his defining albums, made at his peak (around 1947), was Yardbird Suite.
The chords sequence starts with a ii, V7 (intro) and then the I. In the 3rd bar (at the melody b flat) the chord is Fm (F,A, C) i.e. the iv chord. But is quite clashy with the Bb. Then we see use of Bb7 (blues flat 7th of the C scale - dominant chord). This progression suggests a ii, V, I sequence but it does't change key but goes back to C7 chord. Its a fairly common technique in jazz.
Next system begins with a C7 (i.e. Ist chord), bVII7, VI 7 (interesting as A would normally be a minor chord). In this case its dominant. This was often used to give a stronger sound, then back to II 7 (dominant again) going to the dominant.
The next system begins with an Em i.e iii, which moves down a 5th to A7 (VI the chord) then down another 5th to Dm (ii). Again this sequence almost sounds like a ii, V, I sequence but its doesn't change key - sticks to the D minor and then back to G7 (V7). The next system repeats the key chords (but omits the iii, VI, ii sequence.
However, in the fifth system , we have Em (iii) followed by F#m7 b5 - in line with the E minor harmonic scale. Next is B7 followed but he iii, VI 7 , ii - this time moving back to, iii b5 7 , VI 7 , II7 (stronger movement), then ii, V, I (relief!). This is followed by iv to Bb 7 and back to I 7. On the home run, Bb7 (i.e. bVII 7), VI, then a step down II (dominant again), ii (minor this time) to I, and finishing with a ii, V7, I progression.
So does this meet the criteria. Well it certainly is looser than the blues, has more interesting chord changes and goes way beyond the blues structures and progressions. Is it happy and based on improvisation? Here's a Youtube video of the Charlie Parker original. There are several solos based on improvisation before returning to the melody- saxes, muted trumpet, electric guitar, piano. Sounds happy to me!
Did Charlie Parker work this out as he was improvisating or was it instinctive? Charlie Parker apparently once said:
‘You’ve got to learn your instrument. Then, you practice,practice, practice. And then, when you finally get up there on the bandstand, forget all that and just wail.’