Contending that the defendants in a commodities/fraud case forfeited the work-product privilege because their attorney allegedly “commandeered” the drafting of an expert’s report, the Commodity Futures Trading Commission demanded prior versions of the report and records of communications between the lawyer and witness. In 2010, the work-product privilege provided by Federal Rule of Civil Procedure 26(b)(4)(B) and (C) was extended to cover drafts of reports from experts and — with three …