There are some extremely intelligent people in business (by which I mean high IQ, not just wise or experienced), but you tend to find them in the corners of the business landscape [...] Steve Ballmer—for instance—might deafen you, but he would not dazzle you.
No comment on his ability to dazzle, but Ballmer certainly does have a high IQ:
In high school, Ballmer scored a 1600 on his SATs and was a National Merit Scholar.
As a college sophomore, Ballmer finished in the top 100 in the prestigious Putnam national math competition, and ended up graduating magna cum laude in applied math and economics.
No comment on his ability to dazzle, but Ballmer certainly does have a high IQ:
http://www.thecrimson.com/article/2002/6/4/personable-ballmer-leads-college-extracurriculars-microsoft/