I spent an hour on my hunter trying it. Furthest I got was Crota downed once. The 2nd time I'd go after sword bearer was when something would go wrong - mainly: unless I blew rockets on him he would take to long to drop. It's doable but dropping Crota twice the 2nd and 3rd sword would be the most challenging part I think. Once I stock pile more heavy and have the spare time I'll dedicate a few hours or so (someone with more time on their hands will probably beat me to it).