I think people often misconstrue stance and guard. There are only really two stances, orthodox and southpaw. There are a few guard styles, with many slight variations on each one. 'Peek-a-boo' (your average gloves in front of face), cross-armed & the philly shell (which is actually just a variation of the cross-armed guard that has been developed into a more fluent style). Good boxers tend to master one style. Great boxers can move between in an instant.