As the Senate Republicans’ leader, Mitch McConnell launched an experiment of sorts during the Obama era. It was a strategy without precedent in the American tradition, and it was arguably a historic gamble that wasn’t guaranteed to work. But the Kentucky Republican and his allies did it anyway.

And as the calendar turns from November to December, it’s worth appreciating that last month was arguably the most informative to date when it comes to the results of this experiment – it was a month that crystallized the ways in which the GOP gambit was an extraordinary success and the ways in which it failed in ways McConnell didn’t expect.

McConnell’s master strategy was elegant in its simplicity: after his party was soundly rejected by voters in 2006 and 2008, McConnell came to believe recovery was dependent on unprecedented obstructionism. Republicans, the GOP leader decided, would simply say no to everything – regardless of merit or consequence, even when Democrats agreed with them.

The point, as McConnell has acknowledged many times, was to deny President Obama and his allies the all-important cover of bipartisanship – when an idea enjoys support from both parties, it’s effectively the Good Housekeeping Seal of Approval for the American mainstream. But if Republicans embraced blanket opposition to literally every Democratic proposal, the public would assume Obama was failing to bring the parties together behind a sound, moderate agenda. The gridlock would be crushing, but McConnell assumed the media and much of the electorate would simply blame the White House, even if that didn’t make any factual sense.

It worked. The American legislative progress has turned from dysfunction to malfunction over the last four years, creating a Congress that fails to complete even routine tasks, and those responsible for creating the worst governing conditions since the Civil War were broadly rewarded by voters. Obama went being from the popular, post-partisan leader who would repair the nation’s ills – an FDR for the 21st century – to the president with a meager approval rating who hasn’t signed a major bill into law since 2010.

As the results came in on Election Night, Vox.com made a compelling case that described Mitch McConnell as “ the greatest strategist in contemporary politics .”

It’s tough to disagree, right? Republicans intended to destroy the American legislative process, and they did. Republicans set out to exacerbate partisan tensions, and they did. Republicans hoped to make Obama less popular by making it vastly more difficult for him to get anything done, and they did. Republicans hoped to parlay public discontent into electoral victories, and they did. Republicans made a conscious decision to prevent the president from bringing the country together, and they successfully made the national chasm larger.

There’s just one thing McConnell & Co. forgot: a gamble like this can be a strategic success and a substantive failure at the same time.

Consider this report , which ran on Thanksgiving.

President Obama could leave office with the most aggressive, far-reaching environmental legacy of any occupant of the White House. Yet it is very possible that not a single major environmental law will have passed during his two terms in Washington. Instead, Mr. Obama has turned to the vast reach of the Clean Air Act of 1970, which some legal experts call the most powerful environmental law in the world. Faced with a Congress that has shut down his attempts to push through an environmental agenda, Mr. Obama is using the authority of the act passed at the birth of the environmental movement to issue a series of landmark regulations on air pollution, from soot to smog, to mercury and planet-warming carbon dioxide.

It seems counterintuitive, but President Obama simply doesn’t need Congress to advance one of the most sweeping and ambitious environmental agendas in generations.

With this in mind, McConnell’s strategy worked exactly as intended, producing the precise results Republicans were counting on, but the plan failed to appreciate what an ambitious president can still do with the powers of the presidency.

It’s not just the environment, of course. McConnell’s plan was also intended to destroy immigration reform, which was effective right up until Obama identified a legal way around Congress, helping millions of families in the process. Jon Chait added

The GOP has withheld cooperation from every major element of President Obama’s agenda, beginning with the stimulus, through health-care reform, financial regulation, the environment, long-term debt reduction, and so on. That stance has worked extremely well as a political strategy. […] The formula only fails to work if the president happens to have an easy and legal way to act on the issue in question without Congress. Obama can’t do that on infrastructure, or the grand bargain, and he couldn’t do it on health care. But he could do it on immigration.

And the environment. And in addressing the Ebola threat. And in targeting ISIS.

The irony is, had McConnell pursued a different approach, he could have advanced more conservative policy goals. If Republicans had worked with Democrats on health care, the Affordable Care Act would have included provisions with the right. If McConnell were willing to deal on immigration, Obama would have endorsed a more conservative approach than the executive actions announced two weeks ago. If the GOP made an effort to work with the White House on energy, Obama’s environmental vision would almost certainly have more modest goals.

Republicans might have been better off – which is to say, they would have ended up with a more conservative outcome – if they’d actually compromised and taken governing seriously in some key areas.

But McConnell thought it’d be easier to win through scorched-earth obstructionism.