| Often with a wider spacing of the fret there comes a "micro harmonic" that allows for a subtle change in note or sustain. When up there, you want to get your finger off the string faster than in the middle of the neck.
There was a discussion about the "bending" of harmonic notes awhile back & some of that had issues of where on the neck you are working. This is one area where a fret-less becomes extremely valuable becasue there is also no chance of touching the string to the fret. With some harmonic oriented material you may want to raise your action a fraction to prevent drowning the harmonic by fret contact (a very, very tiny bit of course).
Your strings really do need to be new. One of the more significant things about playing close to the bridge is that with the increased tension comes an easier 'feel" to get off the string before drowning the note.
Practicing melodic harmonic-only riffs will give many folks a feel for the soloist element in things like Jaco's work. (IMO) His stuff sounds great not because it's complex construction but because of a feel that he had worked on for many years. It's not something most people can emulate in a few weeks. Remember it's the spots between the notes that make just as much an impact as the notes themselves.
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Paul Tutmarc: Inventor of the Electric Bass - 1931.
1st Electric Bass "Serenader":. L.D. HEATER Co. 1948
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