Dudes, you will find some times where Jaco was looking at the neck, no doubt.
But are you arguing that he relied on this?
If so, I wonder what he did when he was hired to sight read complex passages. I have been hired for this and I personally guarantee you that Pastorius did what I did...use my ears, forget the whole lined vs unlined debate. Otherwise, he was cut out of a lot of work. It's happened to me. I learned.
I guess for those of you who believe the lines, dots, etc are necessary and it is worth arguing about whether it should be lined or not, I wonder why this is necessary for us bassists and not for the huge majority of the millions of musicians of other instruments who don't need these crutches?
Are we really handicapped because we are bassists? Only bassists need this because we are somehow inferior?
Ladies and gents, the whole lined vs unlined debate would be seriously laughed at in the general fretless community of musicians.
I'd hate to argue that we need to argue about this because we are bassists. I would be even more uncomfortable arguing that some of our greatest bass musicians needed lines or dots or whatever.
What was Pastorius missing that all these millions of other orchestral musicians had? How come hundreds of thousands trombone players can play their instrument in tune without dots, lines whatever and Pastorius was unable? He was somehow inferior to all these guys? He chose the bass because he couldn't have cut it on the 'bone?
Yes, you will find some pros looking at their lines or dots or whatever sometimes. However, if that is what they need to do what they do, they are cutting themselves out of a lot of work. Perhaps it's ok. But the average working bassist can't afford that.
That is why I would argue that serious musicians who need music to survive find the whole lined vs unlined debate pretty funny. It's simply not usable at a certain level. Common sense will tell you that. And most fretless instruments in the world don't offer it. It really should tell us something.
Unless we are arguing that because we are bassists, we need this. Which is really rather embarassing. We are often looked upon as lesser than by other musicians, I would hate for us to actively advocate for this in front of all the other fretless musicians who play their non bass instruments without all this paint.
Come on. We are able, let's stop selling ourselves and our role short. We are as good, if not better, we just need to move away from these entertaining but slightly embarassing lined vs unlined debates.
John
*standing ovation* 
