I'm thinking that they are both equal, however, D2 has a lower loft.

No in fact the face does not close at all when you set the club more upright.  A common myth about Titleist woods is that to hit a draw you must close the clubface and to close the clubface you must adjust the club more upright.  Although placing the club upright will help you release the club more, it does not actually close the face.  When you go up in loft you close the face so if you want to close the face try D4 or C3.  Setting the club at a lower loft than A2, which in your case would be D2 would actually open the clubface rather than close it.  It would not affect the ball flight in any significant way compared to A2 but it would lower th eball flight a tad and the ball might not draw as much simply because the clubface was more open.  So in Short:  Higher loft = closed club face, Lower loft = open club face, more upright lie = easier to release club head but not necessarily closed club face, flatter lie = harder to release club bot not necessarily open club face.