agree tht 2d was really off....of course pard may rebid 4h over 3nt and go down still or pard may rebid 2h over 2d and now you may get to 3nt making or south may open 1c and you have yet another auction.
I must say I really find these gib auctions very interesting...even where here 2d seems grossly wrong per GIB bidding system you still have a chance to get to making 3nt.