actually since i last posted here there was interesting thing i learned. From a couple of aerosmith songs as a writing tool i noticed sometimes they will start a song in a minor pentatonic key, shift back 1 semitone, then choose to switch to the major pentatonic key from that particular scale for the guts of the song, then build a bridge from the minor key based on the root of the chosen pentatonic, eg cmaj scale to cmin. As a writing tool u can then move up or down based on the 4th or 5th or u can drop a semitone and go through the same process as you start from. I was messing about the other night after palying the song crazy, and this is what i heard in the structure. If you look to how alot of blues players mix maj and min pentatonic and and chromatic playing this makes alot of sense and has certainly opened alot of doors all of a sudden to me. Not everyone will understand this process, it has taken me eight years, and will probably take another few years before i find exciting ways of executing this knowledge. But maybe it will help someone find another interesting way of musical structure.