An interesting read on the thought process the FAA went through to arrive at its decision. The document attached in the following link for the A5 docket specifically addresses some of the concerns that have been raised in this discussion thread regarding competitive advantage, part 23 certification, removing other items to make the plane lighter, the folding wings, etc...

http://www.regulations.gov/#!documen...2012-0514-0136 then click on the link at the site to view the attached pdf document.