If 1♦ is unbalanced and Pass denies 3 hearts then the only shape that South can have where N-S do not have a fit is 2254. That would make doubling from the North seat even safer.
This would also be a great hand for the skip-bid responses I posted about recently. North could respond 1NT to show a weak hand with both majors. One of these days I will put the thoughts and notes on this together and publish a coherent method here for everyone to pick apart.