This is why bass educators are displeased with me; I state that they are not fulfilling their principle goal which is to teach to bass players what they cannot acquire easily on their own, which is meaningful musical content to work on.
i think this may be less true today than it was when jeff first hit the scene in the 80's and 90's with his magazine articles and stuff, pre internet. maybe i travel in different circles, but pretty much everyone i know has experienced in some way, charlie banacos' approach note exercises (whether from charlie, or a former student or some other source). i know bass players going to Bergonzi's books, approach note exercises, triad pairs, melodic cells, everything in every key etc. transcribing charlie parker and coltrane solos and playing them on the bass and pulling them apart and analyzing and isolating the phrases and playing through the keys. there's just so much info available today its actually overwhelming. not much of this stuff was around back in the 80's when i first started.