Everyone has to get into the old debate about weather standard IQ tests are a true and accurate indicator of intelligence...
I think that is missing point; what Power was REALLY asking is: "does one need to be
intelligent in order to be successfull.
And I agree with him; its not so much about intelligence as it is about FOCUS. I've seen very "dumb" people earning millions and gifted individuals stuff up and end up working in ordinary low paid jobs.
A word on focus: focus not on what you don't want but what you DO want.
Too many people employ certain actions in order to avoid a certain outcome and then end up experiencing that very outcome that they were wishing to avoid.
In other words the subconscious mind ignores words like NOT or DON'T.
eg. Try not to think of eating a chocolate muffin with red and green smarties on it.
You just produced a mental image of the treat ... didn't you!!!