Senators grilled Facebook CEO Mark Zuckerberg for five hours on Tuesday, but the big takeaway was hard to pin down. That’s because Zuckerberg was, too. Summoned to testify about Facebook’s role in the Cambridge Analytica scandal, he shrewdly gamed a flawed format to wriggle out of tough questions, while taking advantage of bad ones to expose the lawmakers’ shaky understanding of his company’s products. In the process, he implicitly made the case that Facebook’s users might be no better off with Congress making decisions about their online privacy than they are with Zuckerberg controlling the knobs.

Did we learn, at least, that Facebook can’t be trusted to fully protect its users’ data, no matter how many times it apologizes and promises to do better? Maybe, but anyone who didn’t already know that just hasn’t been paying attention.

In what could have been a defining moment, Sen. John Thune, a South Dakota Republican, cited a recent Wired story about the company’s “14-year history of apologizing for ill-advised decisions,” then asked Zuckerberg how Tuesday’s apology was any different.* The pointed question exposed an obvious weakness in Zuckerberg’s position as he tries to convince legislators and the public the company does not require heavy-handed government oversight. But, like several such questions in Tuesday’s hearing—the first of two, with a Housing Energy and Commerce Committee hearing to come on Wednesday—the moment was too fleeting to really discomfit the Facebook chief or to elicit much candor from him.

That’s partly because Zuckerberg came both well-prepared and rigorously trained to stick to his script. “We made mistakes”; “need to take a broader view of our responsibilities”; “we’re already taking action”; “started in a dorm room”: Reporters who’ve been covering Zuckerberg’s latest media blitz could have written much of his testimony on a bingo card before the hearing began. (One Twitter user actually attempted it.) Though Zuckerberg hasn’t quite shaken a reputation for awkward, sweaty public appearances, he’s actually become rather adept over the years at conveying earnestness while skirting tough questions. He did that with Thune’s question about his history of apologizing: “We’re going through a broader philosophical shift in how we approach our responsibility as a company,” he said, adding, “We try not to make the same mistake multiple times.”

Reporters who’ve been covering Zuckerberg’s latest media blitz could have written much of his testimony on a bingo card before the hearing began.

Another culprit in Tuesday’s snore-athon was that many lawmakers clearly lacked a firm grasp of how Facebook works. “So, how do you sustain a business model in which users don’t pay for your service?“ asked Sen. Orrin Hatch, the Utah Republican. Zuckerberg could hardly contain a smirk as he replied: “Senator, we run ads.”

Lawmakers’ fumbling allowed the Facebook chief to show off another tool in his evasion arsenal: Exploiting flaws in the question, or weaknesses in the questioner’s understanding, to parry uncomfortable lines of inquiry. Sen. Deb Fischer, a Nebraska Republican, asked a question about how many “categories of data” Facebook collects on its users. Some astute folks on Twitter inferred that she was trying to press him on media reports about the many different types of user data that go into Facebook’s ad targeting. Taken literally, however, it was a nonsensical question, and Zuckerberg was happy to treat it as such. Multiple senators made the mistake of asking questions premised on the claim that Facebook sells users’ data to advertisers. It doesn’t really do that, and Zuckerberg seized on that point each time. The Washington Post’s Alexandra Petri summed up these portions of the hearing aptly:

senator: my aides have given me this complex multi-part question to read to you in a halting and uncertain voice

zuckerberg: oh no don't worry about that, our new motto is 'we fixed it'

senator: that sounds wrong but i don't know what to ask — Alexandra Petri (@petridishes) April 10, 2018

But the biggest obstacle to productive questioning was the format of the hearings themselves. The joint hearing of the Senate’s Commerce and Judiciary committees featured questions from 44 different senators, a frustrating number of whom asked Zuckerberg questions that others had already asked. Each was allotted just a few minutes—ample time for a bit of grandstanding, but not nearly enough for a sustained line of follow-up questioning on complex topics.

Make no mistake, there was some decent grandstanding. Some of the most entertaining came from Sen. John Kennedy, a plainspoken but sharp-witted Louisiana Republican, who told Zuckerberg, “Here’s what everybody’s been trying to tell you today, and I say this gently: Your user agreement sucks.” Kennedy went on to suggest that Zuckerberg “go home and rewrite it” so that it actually informs users of their rights rather than simply covering Facebook’s behind. It’s a fair suggestion, albeit one that neither Facebook nor any other online service provider seems likely to heed unless compelled to do so. But it neither demanded nor really even allowed for an illuminating response.

One of the only senators to throw Zuckerberg off-script was Dick Durbin, the Illinois Democrat. He asked the CEO whether he’d be comfortable sharing with the committee what hotel he stayed in last night. After an awkward laugh and pause, all Zuckerberg could manage was a sheepish “no.” Durbin proceeded to ask whether Zuckerberg would share the names of people he’s messaged in the past week. Zuckerberg demurred again. “I think that may be what this is all about,” Durbin said. Point: Durbin.

Perhaps if Sens. Durbin or Kennedy had been granted more than a few moments, they would have followed up their zingers with tough questions.

Perhaps if Durbin or Kennedy had been granted more than a few moments, they would have followed up their zingers with tough questions.

More likely, someone like California Democratic Sen. Kamala Harris could have used additional time to grill Zuckerberg on some of the holes in his testimony. A prosecutor by trade, Harris made the most of her time interrogating Zuckerberg on what the Cambridge Analytica scandal revealed about Facebook’s priorities. “A decision was made not to notify the users” when Facebook learned in 2015 that Kogan had leaked users’ data to Cambridge Analytica, Harris noted. “Were you part of a discussion that … resulted in a decision not to inform your users?” Zuckerberg claimed feebly that he didn’t remember such a conversation. That wasn’t a gaffe by any measure, but it certainly didn’t help the CEO re-earn anyone’s trust.

But even on the rare occasions, like that one, when he was cornered, Zuckerberg had only to stall for a minute or two and he’d be saved by the bell.

The most notable instance came when Sen. Richard Blumenthal, a Connecticut Democrat, pressed him on whether Facebook’s handling of user data had violated a 2011 settlement with the FTC. That FTC decree required Facebook to obtain users’ “express consent” via “clear and prominent notice” before sharing their data in new ways. Blumenthal noted that tens of millions of Facebook users had their data shared with researcher Aleksandr Kogan—and, ultimately, with Cambridge Analytica—not through their own consent, but through that of their friends. Zuckerberg weakly murmured the company’s official stance that those users had in fact somehow technically consented given its policies at the time. It was a baffling and barely defensible claim, but one that Facebook clearly feels it must make lest it face steep fines as part of a new FTC investigation. He then quickly pivoted to his “broader view of responsibilities” line to run out the clock. An intriguing foray into questions of monopoly and competition from South Carolina Republican Lindsey Graham was similarly abandoned in the face of a Zuckerberg filibuster.

That the hearings failed to yield any dramatic moments of truth may disappoint critics, but it shouldn’t surprise us. Sen. Bill Nelson of Florida, the ranking Democrat on the Commerce Committee, correctly predicted on Monday that the sprawling format would thwart attempts at substantive interrogation.

It’s too soon to say that Facebook has escaped unscathed. It’s possible that one or more of his answers—or non-answers—could come back to haunt him. And several senators made it clear they intend to pursue at least some form of legislation aimed at Facebook and other social networks. More, and perhaps more astute, questions will come Wednesday when the House gets it turn.

But a few awkward moments in the course of five hours—and a handful of (mostly Democratic) senators motivated to pursue modest privacy legislation—was close to Facebook’s best-case scenario entering Tuesday’s hearings. Facebook’s stock leapt 4.5 percent on the day, if that tells you just how worried its investors are now.

Humility and charm may not come naturally to Zuckerberg, but finding the loopholes in a system and exploiting its flaws certainly does. And the Senate committee hearing, it turns out, was ripe for hacking.

*Correction, April 11, 2018: This article originally misspelled Sen. John Thune’s first name.

Read more from Slate on Cambridge Analytica.