CBS OnDemand, which rents commercial-free episodes for a modest fee as low as 99 cents, but which must be viewed within 24 hours of downloading to a PC, is one experiment. (Those CBS downloads reveal just how much time commercials occupy in the traditional broadcast: with commercials stripped out, a 60-minute program may run as short as 41 minutes.) The abundant network program offerings at iTunes, which cost $1.99 but do not go poof after a set time, is a work in progress, too. An industrywide hardware standard that could immobilize remote controls, and the related Philips pay-to-surf proposal, are also in the mix of possible responses to the industry's quandary.

I have not paid close attention to the online offerings of single television episodes because my DVR works well and the fast-forward function on my remote works very, very well. (The button I've programmed to perform a 30-second skip is holding up beautifully, even though it is pressed as emphatically as a hospital button connected to a morphine pump.) Why would I ever buy what the DVR effortlessly records at no cost? Even if I were to feel a twinge of concern that by skipping ads, I am violating an implicit contract that Mr. Kellner asserted exists between broadcaster and viewer of ad-supported television, I take comfort in the knowledge that no such contract exists.

James Boyle, a law professor at Duke University, said that broadcasters offer a program knowing that only a fraction of the audience watches the commercials. Advertisers, he added, buy nothing more than "an option on a probability," and the viewer is no more obligated to watch every commercial than a driver is obligated to read every billboard.

The trickiest legal issue posed by DVR's is not ad-skipping, but something even more basic: the right to freely make a copy of a program for personal use in the first place. My assertion of an inalienable right to fast-forward through commercials would be rendered moot if the creators of the program that I am racing to rejoin were permitted to fully exercise the protections of copyright and impose control over the copying of their creative work.

Since the dawn of the videocassette recorder designed for home use in the mid-1970's, we have copied copyrighted television programs with impunity, enjoying the "fair use" exemption granted for this, a private, noncommercial purpose. The legality of home copying based on "fair use" was enshrined in a Supreme Court decision, Sony Corporation v. Universal City Studios Inc., handed down in 1984.

That decision addressed copying with a Betamax videocassette recorder, and it remains the key decision that protects copying with DVR's today. But the more one looks at how the court arrived at its decision in the Sony case — a 5-to-4 squeaker — and at how recording technology has changed and new business opportunities have opened since then, the more difficult it is to see how a majority of the court could possibly uphold the same position today.

The courts uphold "fair use" only when it doesn't harm the commercial value of the copyrighted work. At the time the suit was brought, skipping ads during playback on a clunky tape machine was hardly worth the considerable trouble. At the trial, survey data showed that only about 25 percent of recorded ads were skipped. In the face of testimony by Fred Rogers of "Mister Rogers' Neighborhood" on PBS, who welcomed home copying of his program, the movie studios that brought the lawsuit failed to convince the judge that VCR copying of televised movies was hurting their business.