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until you can play without thinking with either brain. Once it's second nature you will move much mo' smootha along that neck.

I don't know if you ever tried what I once suggested about learning the neck. Most people learn to fret from the nut until they hit the body. That has a place for learning scales. But if you learn the neck in a "planar" fashion at an angle. In your case, on a 4 string bass, your first note on an open string on the top string is a G. Find every G on every string all the way to the 15th fret on the 4th string. And work on playing G after G after G as fast as you can. That's how you learn to not play everything based around the 3rd fret. Then work on playing intervals and patterns in every key and in every position on the neck. About 95% of the bass players I ever knew played almost nothing but root notes and in the same place on the neck. So to relate to the dominant 7 that was the topic, using C as the example, play C E G Bb Bb G E C, so walk up the chord and back down. Over and over, faster and faster. Then move your hand up the neck and find the next position and do it again. Also remember that you don't have to play all the notes in the same octave. You can play C3 E2 G2 Bb3 or whatever. That adds flavor.

Also watch THIS VIDEO and pay close attention to Victor Wooten explaining "wrong" notes. Watch it with whichever brain you want, but try to focus on the message. It's great stuff by one of the best out there. It will help you with "flavor". Try hard to use those scales and such and try to not turn into a boring "root notes only" bass player. You are allowed to use 3rds and 5ths. It's in the rules!!