Hi
Thanks for the response but I think you misunderstand my question. The keywords I mentioned were made-up to test the system so we could assess it's accuracy & value. They should be easy to rank for because they don't appear anywhere else.
We ran reports on ridiculous, made-up words that should be easy to rank for due to their low competition, against famous brands & historical characters that are highly contended. SEOmoz results claimed all our keywords (silly and genuine) rated between 54% to 65% "difficulty". Hardly more than 10% variation.
Compare that to the data on search volume and competition that I get from Google (for example) on the same keywords. The keywords of historical characters rated massively more competitive than the silly made-up keywords - as you would expect.
A perfect proof of this disparity is the phrase Perspex Underpants. SEOmoz claims the phrase has a 63% difficulty rating but if you google for _Perspex Underpants _you'll notice this very question ranks on the first page of organic results. That suggests that 63% difficulty is, in reality, rather easy.
My question, therefore, is are SEOmoz's difficulty ratings wildly inaccurate or am I using the tools wrong or mis-interpreting what they say?