I've been reading the HOUSE BEAUTIFUL website today, and ran across this quote from designer Peter Frank.
Tell me what YOU think about it, and I'll throw in MY 2 cents a little later.
"I find rules and guidelines are for the faint-of-heart and basically worthless. When I read lists of "Always do this" and "Never do that," they never make much sense to me. A very good decorator told me that all four legs of a piece of furniture must always sit within an area rug. That's absolutely right, except when it's absolutely wrong. I have both situations in my house, and both are correct."
---Peter Frank in an interview