Congressional Staffers Testifying as to Legislative Intent

The taxprof blawg reports all this, but I'm summarizing:  There's some dispute over a tax statute in a bankruptcy proceeding. One party in its 100+ page brief submits affidavits of Congressional staffers as to what the law means:  the good stuff starts around page 52.  Another brief is here.

The government's opposition is here.  It includes (around page 25) a letter from Senate Legal Counsel objecting to the affidavits.

Folks, imho this is interesting, but insane.  An affidavit from a staffer, 10 years after the bill was enacted as probative of meaning??  Don't get me wrong, if this were a private contract, and you had ambiguity, I could see getting it in through the parole evidence rule, but.... I don't think that's what this is.  Apparently, though, there's a lot of money at stake, and so why not try.