Shawn,
I doubt that the FAA is struggling with anything. It is Bell that is trying to wag the dog.
The King Air you mention is/was certified under a SFAR.
I can see EC asking for the EC 145 to be in Part 27 soon as it is only 400 lbs heavier than an IGW 429, what the hell who cares.
Bell started with a clean sheet and screwed up. How difficult would it have been to comply with Part 29 in the beginning?
The farce is the equipment required for the IGW. WTF?
The line has always been in the sand.
SFAR 28 anyone?