Thanks, Shawn. When I used the phrase "switching sides", I was referring only to the fact of leaving the army of one side and joining the army of the other side. Unless a man wrote a letter or memoir about his war experiences, there is no way of determining his sentiments, so I don't even try.
In the same vein, I don't automatically assume that because a man served in the Confederate army, he was pro-secession, pro-South or pro-slavery. The majority of men who served in the Confederate army were enlisted under the Conscript Act. Again, absent anything written by those soldiers, there's no way to determine whether they were compelled to serve, or if they served voluntarily.
So I agree completely with your note of caution about ascribing motives. And I get a little perturbed when people react with shock and horror at finding a "Yankee in the woodpile" among their ancestors. Unless that Yankee left a written document explaining his motives, people have no business trying to pass judgment on him.
Thanks, Shawn, as always, for your insightful posts.