I like 3D here. West needs very little from pard to get to a slam. The cuebid will not be passed and conveys the strength of the hand. If pard has a four card spade suit, she will bid it. If pard's strength lies in clubs, then she will rebid the club suit. Then there is the preference to bidding 3HTs. Once a trump suit is confirmed, then I look to slam. If pard bids 3nt, then we know that her points are probably in diamonds. So, duplication of values doesn't excite me. To me, bidding after pard's call of 3NT is the problem for me.
