Actually as I review the dates of rank, Sedgwick does have an earlier date of rank to Maj Gen (4 Jul 62) vs Slocum (25 Jul 62, so he would be senior. My thinking was based on the fact that Slocum was senior on the battlefield before Mead (and Sedgwick) arrived.
From what I've read Sedgwick was considered very capable, but not very aggressive. When he died at Spotsylvania Courthouse in 1864, Grant said he was a tremenous loss, and Lee expressed sadness at the loss of an old friend. Interestingly, he died leading pretty bravely (or foolishly), walking around in the open, chiding his men for running about to dodge bullets.
Anyway, I guess the point remains the same, it's unclear whether any (temporary) Union commander after Meade's fall would be any more aggressive at pursuing Lee. I guess one could concoct a supposition where Sedgwick does pursue aggressively, but you'd really have to get into his mindset to argue persuasively that's likely.
From a quick look on Wikipedia, both Slocum and Sedgwick appear to have the same date of elevation to rank of Major General. I am not sure if Slocum had some kind of tiebreaker over Sedgwick. I am not sure that either one of them is likely to do better than Meade, and if you assume that Grant still rises to position of The Big Guy, it may make little difference as to whom (Meade in OTL, or Slocum / Sedgwick in TTL) is named commander AoP.
jahenders - I suppose I agree the ANV could have taken some more hurt during the retreat, so I need to either get back to work or update my sig.
