Ya know, there are "obvious" questions embedded in surveys to weed out respondants whose participation should be precluded due to a lack of common sense or intelligence.

A couple of years ago, I underwent four hours of psychological, apptitude, IQ, problem solving, etc, testing for an executive position in a highly public profile government venue. The sheer number of inane questions annoyed me, until I realized their inspersion was simply aimed at doing just that. Same deal as the phrasing in some surveys... and repeating the same questions phrased differently.

Fact is, properly designed surveys are an art. So is not getting pissed off. And, I have an Irish and French temper. But, I made it to the finals. (Unfortunately, they really did want a dancing puppet instead of a hard working and talented engineer. Otrherwise, I may have stood a chance.)