There were also issues like "Bounty jumpers" who enlisted then deserted to enlist some where else.
States were paying $300 per enlistment so it was pretty profitable.
Also, record keeping wasn't all it could have been either. I'm currently reading a history of the 6th Michigan Calvary (one of Custer's regiments) written by it's commander and he claims that none of his after action reports for the 1864 campaign made it into the official record.
As for black in Confederate service a professor in Ga was tracing them and had compiled a list of 8000+ free black volunteers by name and regiment. No matter what Congress said, the issue was states rights with slavery just being one of several issues we are STILL dealing with.
Solus has found out my secret. Wiki is your friend ! I have occasionally found it a little shallow, but I've never found an entry that was wrong.