Ok, what happens if I believe that a layout is what I want, and then when I go and apply it, it breaks something fundamental? Is there a way to revert to the default layout?
Yes if you go back to the advanced layout page. Where you click to download the layout there is an option to download previous layouts. It does make backing out very handy.
There is a history link. When you click this it will show all the files you uploaded and the date stamp of when. You can download one of these and re-upload it to restore your site to before the changes.
--
Six Demon BagJack Burton: Hey, what more can a guy ask for?
Egg Shen: Oh, a six-demon bag!
Jack Burton: Terrific, a six-demon bag. Sensational. What's in it, Egg?
Egg Shen: Wind, fire, all that kind of thing!