I'm using the Twenty Eleven theme for some web sites. I've installed numerous plugins that extend and modify the theme. I'm concerned that when it comes time to upgrade WordPress I'll lose my modifications.
I've seen some comments about creating a child theme to avoid losing my mods. but the articles only talk about adding a style.css file in the child folder.
Is there a good reason not to just copy the entire twentyeleven folder to another named folder and use that 'theme?'