Here is an example of what I mean:
With no one vulnerable at matchpoints, partner opened two clubs (strong) after three passes. I made the waiting bid of two diamonds, and partner bid three clubs with ♠ A9 ♡ AK8 ♢AKJ ♣ AK764. That is to say, he had what I call a "weak preference" for clubs.
I raised three clubs to four clubs with ♠ 865 ♡T765 ♢Q952 ♣ QT, which forced us into five clubs. With partner's hand, I would have not bid three of a minor after the two club opening with only five in the suit, because it takes 11 tricks to make game. So I presumed partner had six clubs, and a strong preference, meaning that my QT was more than adequate support. I also inferred from the three club bid potential weakness in one of the majors. (This was a relatively new partner, and we had not discussed these issues beforehand.)
Partner wanted me to bid three hearts to show my four hearts (even though he didn't have four hearts). His second choice was for me to bid three no trump instead of four clubs. We were outscored by other pairs who made overtricks at 3NT and shared a bottom.
Was it a good idea for partner to explore alternative contracts with his hand? Or should he have gone straight to 3NT instead of sending us on a wild goose chase?
Edit: I now realize why I was confused. I had always thought that the opener's rebid (after a two diamond response) was "to play." That is, he wanted to play in clubs, presumably with a six card suit (for which my QT was adequate support) and shortness elsewhere in the hand. Apparently his three club bid was "for show," only five clubs not necessarily weakness elsewhere. I expected him to rebid 3NT "to play" with his holding.
Which is the more reasonable assumption/posture, rebid to "play" or rebid "for show."