Furthermore, additional material recorded for, but not used in Bitches Brew (mainly rehearsal takes and unedited performances of the six album tracks), is not included in this set.

When questioned by Paul Tingen why most of the material in fact was not recorded either for or at the same sessions as the original album, re-issue producer Bob Belden clarified how the team's thought process went.

According to him and the engineer, all the songs Miles Davis recorded between August 1969 and early February 1970 used very similar line-ups to those on Bitches Brew, and the main thing they all had in common was the emphasis on keyboards.

It was not until late February 1970 that Davis refined his concept by dropping the multiple electric pianists for a more guitar-heavy sound.

Though the unreleased selections are distinctly inferior to those released on Bitches Brew, "Yaphet," "Corrado," and "Trevere" are intriguing jam sessions that reveal much about the creative process between Davis and producer Teo Macero during recording....