If the Senate filibuster changes envisioned by liberals would accelerate chamber business like a sports car, the compromise reached Thursday is closer to a bicycle.

To be sure, the deal reached between the chamber’s leaders gives Senate Majority Leader Harry Reid a bit more power in setting the agenda, but it falls far short of what other Democrats and liberal groups wanted. Still, the Senate easily passed two resolutions Thursday night to enshrine those changes in the rules.

In theory, the Nevada Democrat could use the new rules to bring up almost any piece of legislation, as long as he allowed Republicans to offer at least two amendments of their choosing. But in practice, political pressures may make him think twice before employing that tactic.

One senior GOP aide expressed doubt that Reid would regularly use the new power to sidestep filibusters on motions to proceed. After all, he would be giving the GOP the power to have a roll call vote on any topic, and Republicans have not been shy about pushing amendments they know put vulnerable Democratic incumbents in a difficult spot.

Of course, the new maneuver could also set up a quandary for Minority Leader Mitch McConnell. He would control the right to offer the Republican amendments, and the 45 members of his conference would undoubtedly be interested in getting their chance to address their issues.

For instance, McConnell’s colleague from Kentucky, fellow Republican Rand Paul, frequently seeks to offer floor amendments that face overwhelming defeat and are not popular even among the majority of Senate Republicans. If McConnell, rather than Reid, is perceived as blocking Paul’s amendments, it could cause trouble for him back home as he seeks a sixth term in 2014.

Steven S. Smith, a Senate procedural scholar at Washington University in St. Louis, called the overall package “a very modest change.” He noted that the agreement eliminated a draft provision from Sens. Carl Levin, D-Mich., and John McCain, R-Ariz., that would have given committee chairmen and ranking members more power to pick floor amendments under the process.

“This may be a bow to unhappy Steering Committee types who may not have liked the previous draft that gave formal leadership control of the amendments,” Smith said. “There will be some confusion about how those amendment opportunities will be allocated within each party.”

Of course, the change is only temporary, expiring at the end of the 113th Congress. The permanent rules change Reid and McConnell agreed to may be even less likely to work. The two agreed to create a “bipartisan” motion to bring bills to the floor more quickly. But that would require the leaders to be in agreement on what should be debated on the floor, and it could prove politically difficult for both.

Obvious candidates for this procedure include bills reauthorizing defense and intelligence programs. But both Reid and McConnell would have to tread carefully in publicly moving a bill that even a small faction of their caucus objects to. The political peril may be more dire for McConnell, who has been trying to head off a challenge from the right in his re-election campaign. Signing off on bipartisan deals might not help him in that endeavor.

The leaders also agreed to informally try to force senators to use debate time on the floor. But how that deal will work in practice remains open to interpretation. The agreement stipulates that if more than one quorum call is called after a measure has overcome a filibuster, the motion to call a quorum will be considered dilatory. That would then allow the majority to call for a vote on the issue. The aim is to end the continuous sequence of quorum calls that are a fixture of the Senate floor.

Senate Majority Whip Richard J. Durbin has long called for a reduction in what he calls “incessant roll calling, which leads people to go to their cable provider and complain that something’s wrong with my channel, the Senate’s not doing anything” when watching C-SPAN.

“If this is a make-or-break amendment or a bill on the floor that means more to me than political life itself, I’d better be willing to come to the floor and express my position on it and stay there and defend it. Bring my allies to join me and make it a real stand on principle,” the Illinois Democrat said. “Right now, it has just become a convenient way to stop the Senate, to stop our action and to really — I think — to thwart what this institution is all about.”

But because the agreement on quorum calls is nonbinding, Reid could decide to not enforce it.

Though many liberals and some conservatives were displeased by the deal, Levin stressed that it would preserve Senate comity because it averted a situation in which Democrats threatened to change the rules by a simple majority vote.

“We just can’t have a situation in the Senate where the majority can decide what the rules are at any given time, even at the beginning of a session,” Levin said. The deal preserves the concept of the modern Senate as a body in which 60 votes are required to get most things done, which has drawn the ire of liberals, such as Sen. Tom Harkin of Iowa, and a host of outside groups. Harkin predicted President Barack Obama’s agenda will suffer as a result of the deal.

“I said to President Obama back in August … and the night before the election, ‘If you get re-elected and we don’t do something significant about filibuster reform, you might as well take a four-year vacation,” Harkin said.

Humberto Sanchez contributed to this report.