Oh no, I didn't mean to suggest these folks are or are not actually "good" managers, just that what they've all got here is congruent with my current understand

Oh no, I didn't mean to suggest these folks are or are not actually "good" managers, just that what they've all got here is congruent with my current understanding of what the literature tells us a "good" manager says and does. I'm not trying to say any of it is accurate either, just pointing out the consistency being likely due to a shared set of sources rather than copying one another outright.