Winstonm, on 2021-June-27, 14:34, said:
I assumed your partner was aware that you may hold only 4 hearts so a robust diamond suit seemed needed for trump control
So why not bid 4
♦?
More generally, I think that it is important to conserve space with strong hands. It's been a while since I have played fourth suit as anything other than forcing to game, but I think that maybe 2
♦, 2
♥ and 2NT might be NF with everything else forcing. Between these there is room to show GF with good diamonds, GF with good hearts and GF with a good club stopper. The remaining bids of 3
♠, 4
♣, 4
♦ and 4
♥ should show very special hands, because you are taking up bidding space when you could have forced instead. Since heart support would have absolutely be shown on the previous round of the bidding these bids would either have to show some supermaximum with 3-card support and overruling the possibility of 3NT (but why not bid 3
♥ anyway, you can bid beyond 3NT on the next round?) or some kind of autocontrol, confirming diamonds.
I can't think of any hand I would seriously expect partner to have for any of these bids. If your partnership allows splinters in partner's suit I assume that is what might be going on here - 4=1=6=2 or the likes.