These all look like substance vs. form issues to me. These "shelters" won't stop until the various state accountancy boards ban the firms which dream this stuff up from practice. What would E&Y do if California banned if from practice within the state?
"It is insisted that the proceedings were all conducted according to the forms of law. Very likely. Some of the most atrocious frauds are committed in that way. Indeed, the greater the fraud intended the more particular the parties to it often are to proceed according to the strictest forms of law", Graffam v, Burgess, 117 US 180, 186 (1886). That the Supreme Court's opinion. That a transaction was made to look legal doesn't make it so.