Janek has mentioned on several posts about woodshedding the exercises in there to free himself from the problems of technique in order to reach that level of playing where you can concentrate on the notes coming out more. Also states he has used these exercises in conjunction with a metronome, taking it all the way to 400 (I guess you could just double 200).
Or at least, that is a paraphrase of what I have read in this forum, probably my favorite forum besides just looking at bass pics
And its kicking my butt....