Interesting study from Princeton psychologist Daniel Oppenheimer, called "Consequences of Erudite Vernacular Utilized Irrespective of Necessity:Problems With Using Long Words Needlessly." (I should mention I have not read, and can't find, an actual copy of this study.)
Took a selection of writing samples (grad school applications, sociology dissertations etc), and changed each of the words to more complex/longer synonyms. Then he gave these samples to 71 students and asked them to judge the intelligence of the authors. The more complex and flowery the language, the dumber the author was assumed to be.
Think about it...
From collision detection