I'm not sure I'm even asking this cause, it sounds beyond ridiculous, how the hell do you spar 2 guys at once?
I recall an interview with Trout & Margarito speaking of their sparring for the Margarito-Williams fight. Margarito said Trout was the only guy who could make Margarito's head snap back during sparring...!!! Trout was used in other sparring/training for Margarito...!!!
Freddy Wak was working with Joshua Marks & Margarito came to spar with Marks...!!! Thread link: http://www.boxingforum24.com/showthread.php?t=21823
even if there was a source. its still in that silly time where rumors are to be treated with a grain of salt at this point. even if it was true its still sparring. in short. just move on. nothing to see here.