Both vulnerable at matchpoints, I dealt and bid one diamond (planning to rebid 2NT) with the following: ♠ JT8 ♡A6 ♢AK76 ♣ AKT4.
An opponent overcalled one heart, and partner bid one spade, showing five. (he would have made a negative double with four.) I followed my plan and bid 2NT. Partner then passed with seven high card points in the following hand: ♠ K7642 ♡K972 ♢J2 ♣ 95. A 3NT bidder got the best score, we got the second best score (out of four pairs), and two spade game bidders (one on each side) went down one (perhaps because the overcaller held AQ95).
Partner later said that he was upset that I didn't raise his one spade bid instead of bidding 2NT, so he miscalculated our point total. While we technically had an eight card fit, I considered our spade holdings to be on the weak side, as evidenced by the failure of the two pairs (we were missing AQ98, four of the top seven cards, despite having eight cards in the suit).
Did it make sense for partner to insist on a major suit game based on the eight card fit? Are there other considerations (such as our rather balanced hands or partner's lack of intermediate cards) that argue for either a no trump or spade game try? Could it be that with the same cards, one contract is better at one form of bridge, and the other is better at another form?
Or could it be that 2NT was the proper (informationally) bid and partner might have used a three level transfer to get me to bid a spade game with three spades and 3NT with two spades?