"How to Ruin a Great Design" reaction

I agree, I can see how something such as an oversized first letter can distract you, particularly when driving, and make the sign generally useless and possibly counterproductive.  Useful designs should be simple, bold, and attention grabbing as a whole.  I also understand how sometimes over perfecting an image or design can take away from it's quality- you may need to just keep it simple and to the point.