@Gregory Eagan If I'm reading this correctly, you're asking, "If I use a capo, do I need to retune my strings so they go back to being EADGBE?" If that's your question, the answer is no. The whole point of using a capo is to change the tuning of the guitar quickly without having to retune the strings. When we see a song that still has chords like C D and E, but with a capo on, what that is telling you, is to play those shapes. The capo makes it to where you can play familiar shapes. While the shapes will be the same, technically the chords will be different, but we follow what the shapes are in this case. If you are asking if you need to retune the strings after you put on a capo, the answer is also no. If the strings are slightly out of tune, you may need to reposition your capo. Another trick that I learned from Tommy Emmanuel, after you put on your capo (with the strings properly tuned first), using your palm of your strumming hand, push the strings down towards the soundhole, or pickups of your guitar. It doesn't need to be very hard, you're just trying to lightly stretch the strings so the capo isn't pulling unevenly on them. Hope that helps!