Duplication leads to fewer tricks

Who said, "It does not make sense that everybody should duplicate efforts when we could be working together"?

In bridge, duplication is having wasted values - high cards opposite shortness, or perhaps ace-queen-doubleton opposite king-jack-doubleton. It often results in fewer tricks being available than the point-count would suggest.

In this deal, North wondered how many "wasted" spade values his partner had opposite his void.