Gamers will want to use the two-trigger stance almost exclusively, as it provides the most physical net coverage.
However, both stances have a glaring flaw: the huge gap between the goalie's leg pads.
Compare NHL 12's post hug (above) to this shot below, taken of Boston's Tuukka Rask:
Goalies in NHL 12 simply do not have proper leg pad form, allowing goals to come pouring in through the open five hole. Facing wrap-around shots, it is often better to manually position the goalie against the post with the left joystick, then drop into a butterfly stance using the left trigger.
The post protect moves in NHL 12 often fail at defending wrap-around shots, but they do possess an unintended use: stopping cross-ice one-timers.
Both post hug animations quickly teleport and "stick" the goalie to the pipe, as if the goalie's pads were made of magnets. Thus any goalie, regardless of size, can rapidly "teleport" across the crease with a post protect move in less time than it would take to manually slide over using the left joystick.
Big, slow goalies can make great use of this artificial mobility boost when trying to cover ground laterally and shut down one-timers.