(BTW, why does blogger.com image upload only support JPEGs? (using "Picasa Hello"))
It's hard to find smart doers, but please, keep on searching for them. If you have the slightest doubt that a potential employee does not fulfill this criteria, don't hire.
The most dangerous species are those who are smart, but don't get things done. First of all, they are harder to be identified as such during the recruitment process. Checking their project portfolio helps (still, they usually are smart enough to fake it).
As opposed to not-so-mart doers, who cause operative mistakes (bad enough), smart no-doers are in the position to make strategic mistakes (even worse). Those are the kind of people who can talk their management into following doomed endeavors which will never result in any marketable product, sometimes putting the whole company at risk. If combined with weak social skills and when put into charge, smart no-doers are best way to get rid of your last smart doers.