with joe douglas, there was a rationale for the lack of information to the runner, and i assume this philosophy was influenced by igloi, at least from what i gather from orville's accounts.
he did require absolute faith in him as a coach. so, when you'd do an all-out 400 at the end of the workout, this was more of an assessment for the coach to gather information, not for an athlete's confidence. you'd have to trust the coach to use this info to tailor future workouts and expectations, so when he'd tell you you're ready to run ?:?? time, you had to assume he was basing this on the information he's gathered through your workouts. i personally liked this, because running was hard enough--i didn't want to have to worry about the thinking part of it. however, this did not work for everyone, and any skepticism generally doomed you...
the other reasons for him not giving splits all the time, and why we rarely ever knew what the whole workout was, were twofold: one, he wanted you to focus on them moment, or the repetition at hand, and not worry about the 12th 400 while you're doing the first; and two, it allowed him to make adjustments without you knowing and worrying like most compulsive athletes will. in other words, joe may have had a plan for you to do 12x400, but if on the 10th one you'd fallen off the target pace, he'd cut the workout short, thereby maintaining the integrity or purpose of the workout, but saving the athlete from worrying or fretting about "not completing the workout." these were some of the ways (and reasons) joe, and i assume igloi, would individualize the workouts...