No specific AMA rule is being broken. Safety should not have to be mandated we should all be building and flying our airplanes with safety foremost in our minds. With that comes the responsibility to follow manufacturers recommendations when it comes to assembling and gearing up our airplanes. Jim stated that he had "exceeded a manufacturers recommended engine size" by doing that and talking about it in an open forum he effectively says that he does not have to follow the manufacturers recommendations for what engine he should have to use. It does not matter that he altered the airframe to increases the strength (who says he did that correctly, maybe he just shifted the failure point to a different part of the structure) he changed and in a potentially detrimental way the airframe.