The dialogue was about how SCOTUS would/could rule on the severability/inseverability of an unconstitutional provision(s) of a statute (HERA 2008).
The dialogue was concerned with the possible invalidation of the entire statute (HERA 2008) on the account that the the single-director structure of the FHFA that is primarily based on the limiting and unconstitutional removal “for cause” provision (See 12 U.S.C. § 4512(b)(2) - https://www.law.cornell.edu/uscode/text/12/4512) may be ruled unconstitutional by SCOTUS.
The issues are: If SCOTUS rules that 12 U.S.C. § 4512(b)(2) is unconstitutional, does it follow that the entire statute - (HERA) - which does not have a severability clause, will be invalidated ("toast")? Can 12 U.S.C. § 4512(b)(2) be severed from the statute without affecting the remaining parts of the statute?
Willet did cite some precedent for striking an entire statute based upon a constitutional violation although his opinion was in dissent the precedent he cited in his opinion still has some standing.
SCOTUS may be able to answer the questions presented.