A decade ago, when the Democrats set out to reform healthcare, they turned to one person above all others: Ira Magaziner. The New England management consultant, charged in the early 1990s with helping then-first lady Hillary Rodham Clinton reform the nation's healthcare system, had a reputation as a genius — at least until his proposals went down to resounding defeat. As the Democratic hopefuls once again broach the subject of healthcare reform, there is no single super-wonk healthcare adviser — no new Ira Magaziner — in sight. The healthcare experts named by the leading Democratic presidential hopefuls are "all big...