When you're keeping a monthly comic book on schedule, there really isn't an opportunity to "redo" pages. On the other hand, if you have serious doubts, there is a window of opportunity to change your mind. Sometimes the window was a little wider than it was at other times:
The explosion in outer space (page 122 of MINDS) Take One. I had given Gerhard the suggestion of doing mirror image atomic explosions, which he did and then wasn't happy with the result (arguing that -- with no "up and down" in space -- it was completely impossible that the explosion would be "up and down": it would have to be a spherical expansion) (which I certainly couldn't argue with but are you SURE you want to start over again from scratch?). Which he did. As Gerhard used to say, "Who WERE those guys?"