Yes, for someone like Doyle Dykes who travels all over the world, being able to read a few notes would not do anything for him. However, in the case of my guy "T", who is an extreme case of "ear playing," (it was fascinating for me that he would play the bass without even knowing string notes let alone fingerboard notes) just knowing the fingerboard notes and a little theory would go a long way. That's why he said it opened up a whole new world for me as he was watching me play the roots and 5ths of I, IV, and V on the bass guitar.

Chris