I read the Ball's Bluff chapters in tandem with Beatie's AOP Vol. III and Jim Morgan's A Little Short of Boats, that is I vetted the material three ways. The treatment of the battle in this higher level regimental history is nearly as granualr as Morgan's battle study, a bonus, I think, for readers of tactical history.
What marks the study as a specimen of its genre, however, is that the social coverage is so much richer. The regiment, especially the ACW's battalion-sized regiments, is a profoundly social (and political) organization. In the general run of regimental histories, the social and personal connections among personalities is sparse and not well documented. The result tends to be a fragmentary narrative in which clusters of personalities bob up and down as the record permits, the emphasis being on movement, action, events. In developing the rich record left by the 20th Mass USV and its officers, Miller offers us the picture of what a balanced regimental history would look like. If I have a quibble with it it has has to do with the underdeveloped political dimension - underdeveloped to my taste, anyway.
Buy one or scrounge one - this is an important work.