Here are some better numbers for Owens: Now that it charges online, The New York Times’s digital revenue more than covers the cost of its newsroom. Digital subscriptions, by my calculations (the NYT doesn’t break these numbers out), already bring in more than $70 million a year, and digital ads are at roughly $155 million (conservatively). That’s at least $225 million a year in digital revenue—and the subscription stream is new and still growing fast, while digital ads are now edging down (though not, apparently, because of the paywall).

2. “Simon’s math doesn’t make sense.”

But Owens uses some wild numbers himself:

A metro newsroom—the newsroom Simon is most concerned about protecting—needs between $50 million and $100 million to provide the kind of big, serious journalism Simon advocates. At $10 a month per subscription (Simon’s figure), the news site would need 416,000 subscribers to cover a $50 million editorial budget.

It’s unclear where Owens comes up with those giant numbers for a metro newsroom. Nobody thinks the Sun will ever have 500 people again (and it’s at least worth noting that the BLS says the average reporter’s salary in Baltimore is $49,000 a year). Owens estimates that its newsroom in 2009 cost between $10 million and $15 million. It’s hard to tell how much digital advertising the Sun brings in, but its site is similar in size to the Times-Picayune’s, which reportedly took in about $6 million in digital ads last year, meaning it would need $4 million to $9 million a year to bring digital revenue up to the level of 2009 newsroom costs.

The Sun newsroom now has just 132 staffers, 48 of whom are reporters or editors in the core metro news area (not including sports and entertainment). That means the $3.6 million a year Owens dismissed could actually pay for increasing the news staff by more than a third (at $80,000 a head, all in), which would make the paper more essential and its subscriptions and ads easier to sell.

As it is, The Sun already has a leaky paywall, put up in October. It took in 11,127 subscribers through March. Those subscriptions cost a minimum of 99 cents a week for print subscribers and $3.99 a week for all-digital. If we conservatively estimate that one-quarter are digital-only subs, that would be a new annual revenue stream of more than a million dollars. And it looks like it’s giving up little or no ad revenue now. After sinking 15 percent or so in the paywall’s first few months, unique visitors have since returned to last year’s level and were down 0.22 percent in April from a year ago, according to Compete (I’ve got questions out to The Sun on these numbers and will update if I hear back).

That million dollars a year is not enough to do much, of course. But it’s better than nothing, and it’s a growing revenue stream—a new source of real incremental revenue that struggling papers can’t leave on the table.

3. “Even if a paywall alone can’t support big-time metro journalism, the early returns show no signs of slowing the bleed out.”

This just isn’t true, and Owens cherry picks some numbers to make paywalls look bad. The Dallas Morning News has 49,000 subscribers? Owens says those don’t really count because they’re probably just print subscribers adding digital. He then says the Morning News’s digital revenue declined 11 percent in the first quarter. That’s not true. That’s the number for its parent company as a whole, and it owns three other dailies. A.H. Belo didn’t break out the papers’ individual ad results. Moreover, Owens doesn’t mention that that companywide decline was mostly caused by some bad comps from a year ago. Here’s Belo:

Excluding the impact of a discontinuation of a revenue allocation to digital and the Super Bowl, digital revenue was flat in the first quarter of 2012 compared to the prior year period.

Even if Owens’s numbers were right and all 49,000 of the Morning News’s digital subscribers are print upsells paying $1.85 a month, the paywall would still be well in the black. Getting print subscribers used to paying for digital access, whether it’s two bucks a month or ten, is a key advantage for newspapers who will need to eventually convert significant portions of their print circulation over to digital.

He also says this:

The Minneapolis Star Tribune has 300,000 print subscribers and is charging a modest $1.99 a week (much less than Simon’s proposed $10 per month for the Sun) and has only 20,000 online subscribers (“only” being relative to our previous points about what’s required to sustain the kind of journalism Simon expects paywalls to sustain). Since the paper is now held by private equity, earnings reports are hard to come by.

Ryan Chittum is a former Wall Street Journal reporter, and deputy editor of The Audit, CJR's business section. If you see notable business journalism, give him a heads-up at rc2538@columbia.edu. Follow him on Twitter at @ryanchittum.