THERE'S NO ANSWER TO THAT....... ( A gospel true story given to Bridgemeister Gibson by the and only " Fenboy "  )

It's the Friday afternoon pairs session of the Sheffield U3A.  The players want to better so are very keen to learn. A hand had just been completed and declarer ( West ) has made 3D plus one for an average on the board.
West is in the process of returning the cards to their slots , while North is writing down the score on the traveller. West muses....then poses a question to North,  a far more experienced player , who he believes might be able to pass on some nugget of advice .
" Do you think I could have done better ? "

" Yes ", came the immediate reply , ".......You should have bid 3NT because it has a 60%  chance of making , given the excellent diamond fit , and a likely spade lead up to your King ."

" But..... isn't bidding 3NT a bit of a risk ? "
" Yes....it may not be safest contract but it scores much better....that's the problem with pairs .  Sometimes you have to make difficult decisions. Sometimes you have to be in what seems the wrong contract to get the right matchpoint score. "
" Well, I wouldn't know about that because we don't play Pairs ! "
 " But you are playing pairs......"
" Oh, I thought you were talking about a bidding system...."