I already talked to Phil about this, but I think I have to defend 2♣ just a little (I am a 2♥ bidder now but was briefly a 2♣ bidder). What are partner's most likely shapes, assuming we open 1♦ on all 4-4m hands? 1345: 2♣ is better 1435: 2♥ is a little bit better, probably. 2434: 2♥ is better 2335: 2♣ is better 2434: 2♥ is better Also, if we bid 2♣, our hand becomes dummy instead of partner's. It's possible that partner is even 1336 with bad clubs. Bidding 2♣ may also get us to hearts anyway when partner has a very strong hand. Anyway, I think it is unlikely that one is dramatically +EV over the other.