Nice quote from Paul Goldstein's Copyright's Highway: From Guttenberg to the Celestial Jukebox (1994) - he says copyright's goal is to give "the public the widest variety of literary and artistic works at the lowest possible price."  (p228) On p224: "The capacity for the celestial jukebox to post a charge for access, and to shut off service if a subscriber does not pay his bills, should substantially reduce the specter of transaction costs.  As these costs dissolve, so, too, should the perceived need for safety valves like fair use. Indeed the economic logic of the celestial jukebox....might produce a law that contains no exemptions from liability at all.... as suppliers oblige their subscribers contractually to pay for now exempted uses of copyrighted material..... One problem with this logic is that the celestial jukebox will not entirely replace traditional copyright markets... Also, some of the 1976 Act's exemptions are there, not because of transaction costs, but because certain uses and users serve socially valuable ends.  The statuatory exemption for classroom performances  of copyrighted works in nonprofit educational institutions is one example.  If copyright owners try to circumvent these copyright exemptions by contract - and there is every reason to expect they will - Congress will have to reconsider the distributional aspects of its copyright agenda and decide whether to outlaw such contracts...."
Goldstein would firmly reject Larry Lessig's notions about copyright extension being unnecessary. He is of the opinion that technological development eroded copyright revenues because eg. people got used to using the VCR without paying for copies because Congress did not act quickly enough to deal with it.  And once people are used to getting something for "free" they will not want to pay for it and Congress is unlikely to make them.  So he says hand out the copyright scope extensions to prevent damage to copyright holders, then assess later the effect.  Lessig on the other hand would say avoid handing out monoplies until the real effect of the technological development can be evaluated.  After all, Jack Valenti was against VCRs and now videos provide huge revenues for the movie industry.
Goldstein's book is terrific.
Goldstein concludes the book on p236: ".. and true to copyright's historic logic that the best prescription for connecting authors to their audiences is to extend rights into every corner where consumers derive value from literary and artistic works.  If history is any measure, the result should be to promote political as well as cultural diversity, ensuring a plenitude of voices, with all the chance to be heard." Hmmm.
Peter Drahos would probably join Lessig, Jamie Boyle, Pamela Samuelson and others in disputing that perspective. I seem to remember Drahos saying that when it comes to intellectual property, "the language of property rights should be replaced by the language of privileges." He also suggested that the holders of "intellectual property privileges" should be subject to such duties as "would maximise the probably that the purpose for which the privilege was first created is achieved."