5
Many people do not worry about it. However, if you were to set up a little test site, with nothing on it except blocks that act as space holders (L,TL, TC, TR, BL, BC, BR, R).
Then you could more easily validate just the theme and not all the content. Validation, in many cases, helps fix problems of this nature. I stand by my improperly nested elements. You may find that the quick fix is as easy as killing a couple tables prior to the footer. Since you really aren't worried about standards it could produce the quick result you are looking for.
ie. Prior to your footer code throw in a couple...
Think of it as the myspace solution. (please don't tell the other theme designers that I am encouraging no compliant practices.... they will tease me for months..
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