I think we're dealing with different axes here. Being compulsively driven towards power isn't the same as being an optimist.

A standard problem is that it's compulsives who are often least qualified to lead effectively who push themselves into leadership positions.

This doesn't make them optimistic, so much as obsessive.

Yeah. On a somewhat related note, my father always says that if you're "too smart" you'll never be rich, since you wouldn't take risks that you knew would have a very small likelihood of paying off.
My own personal theory is that most rich people are in league with Satan, but I don't say that out loud.
Of course, if you're "too smart" you might realise there's more to life than heap loads of cash, but that's another story...

"The basis of optimism is sheer terror" - Oscar Wilde