Great article by Sandra L. Toney posted on Petside.com. She exposes some common cat myths and explains the reasoning. For instance, cats don't always purr just because they are happy...and assuming that could be harmful to your cat.....they also purr when they are in pain or even dying!
And, cats don't always land on their feet....and even when they do fall, they can suffer injuries and broken bones.
Check out the article http://www.petside.com/news/fact-or-fiction-feline-myths-exposed.html, a must read for cat lovers.