Is my recent finding unusual? re: seo'd words 15,000 visitors to site in 2009 - from natural search 5,420 different keywords were used to get there, says Google Analytics 1,157 diff keywords got 2 or more visitors [but only 25 keywords were optimized - nothing else is driving visitors] MORE: 1,047 keyphrases contain the same word 1,912 keyphrases contain another word This all suggests the search engines pick up on many permutations of optimized keywords, am I right?
The important question to ask is what percentage of your organic traffic came from each key phrase? What you probably need to know is the top 50 or so. Yes, of course people will find your site through all sorts of crazy permutations of your targeted key phrases. but the important question is which ones drive the most?
it's also interesting to note that the 5000+ phrases not optimized for, and many, many are 3 or even 6 words long, almost none are long-tail phrases. it's obvious people don't know what they're doing - that is, other than when they type in our 25 phrases.