So, last week I improvised a piece of music and said that it was not quite a proper blues, and then I put together a slow stride piece that also had a lot of bluesy elements, but STILL was not a proper blues...
Then I wrote out [Super Blue] for 
The blues – these developed out of the work songs of my enslaved African ancestors, and retain a storytelling structure about things happening solely in this world, in contrast to the Negro Spiritual, which bridges the gap between this world and the next, and between bondage and freedom. Both bridge the gap between the music of West Africa and the music of early European America, and without the work song and the blues, nothing that has ever been “pop” in North America would ever have come to be.
Instrumentally speaking, the classic blues have a particular 12-bar structure, as opposed to the 16 bars of many common European and European American tunes. The chords, too, fall into a couple of unique patterns, and there is even a blues scale – in more advanced blues than what I have done here, the big tritones that denote quite a lot of African sound hit in that scale quite often.
“BeeCee's Blues” is a proper blues, and gets its name from hitting on B and C together at the beginning, a common element in this type of blues/jazz. The European idea of consonance and dissonance and even major and minor do not always hold in African American music.
Then there are chord substitutions as well, because in African American music, chords with similar elements – say, E flat 9 instead of B flat minor, in the key of F – can readily and easily be substituted due to scale elements from West Africa making F “blue” by flatting the E – or not, in America. The blues scale puts ALL the possible elements in play, so the use of the E or the E flat is determined by the chord pattern, and the blues player in terms of melody improvisation.
Enough said. The blues has to be experienced to be understood. Enjoy.