There is good coming out of Stephen R. Taaffe's Commanding the Army of the Potomac. Although faithful to the major themes and literary conventions of Civil War history as developed at American Heritage during the Centennial, the book is fundamentally about the power of personal relations in Civil War military careers. This central idea violates the meritocratic and apolitical treatments of ACW history in Centennial narratives. That Centennial tendency is beautifully encapsulated in the old saw that McClellan's corps commanders were appointed by the president based on seniority.
This contrary meme may be why the Taaffe has attracted attention (and blurbs) from interesting mavericks like Brooks Simpson and Steven Woodworth.
In his very first chapter Taaffe drops what to conventional readers must seem like four bombshells by sketching the ACW careers of McClellan's four corps commanders. While repeating the (circular) argument that they ranked other generals (Lincoln personally ensured they ranked other generals in the way they were commissioned) he does portray them as - if not polluted - at least compromised.
But it is a stumble as much as a step because the thumbnails Taaffe sketches are woefully incomplete. It occurred to me to present a abstract of Taaffe's sketches, listing the main points, then supplementing them with my own (dark) biographical material. I may also include Beatie's sketches as a third point of comparison. No major contradictions here - just issues of fullness laid out for you in some blog-length postmortems.
Going a commander at a time, you can match my sourced material against theirs. You are encouraged to compare that to whatever accounts you can find in whatever tomes you have at hand. You'll have a very interesting view of how to achieve seniority in 1861 sufficient for a "natural" appointment to corps command.
How to become a corps commander: Taaffe (this post)
How to become a corps commander: Keyes
How to become a corps commander: Heintzelman
How to become a corps commander: Sumner
How to become a corps commander: McDowell
How to become a corps commander: Franklin
How to become a corps commander: Porter