[pescetom]

Thanks to everyone who replied. As can be seen from the poll there is no firm consensus, with all candidate bids getting some votes and being well argued by somebody. For those too polite to ask why I made the post in the first place, I was in West and disliked my (occasional) partner's bid of 3♦, feeling that it deserved a direct 4♦ on the basis described by rmnka447 (to which I would add that East knows he is the only one at the table with an accurate vision of the total tricks). Partner was thinking along the lines well described by mikeh, which did not sway me at the time but on reflection has logic too, so I guess it is primarily a question of being on the same wavelength, as always.