Patrick's post stimulated a lot of discussion here at HubSpot. I contributed one email to the discussion, which Yoav has asked me to post here:
I feel compelled to mention a book that has had things to say to every part of this thread: Managerial Dilemmas: The Political Economy Of Hierarchy. I reviewed it on my blog. It's all about the theoretical troubles in building an organization that works, where everyone is lashed together and focusing on the same goals. Patrick's suggestion sounds troublingly like the piece-rate system mentioned in that book (and in the review). I'd recommend the book, anyway, if you're interested in some fun theory behind these questions.