This appears to hold true for the Gang of 14's agreement, and in this case, the glow of nostalgia adds a coat of whitewash, as well. In the popular retelling, the Gang of 14 came together in 2005 to take the "nuclear option" off the table. The agreement, this legend holds, defused the tense standoff between Senate Democrats, who were filibustering several judicial nominations made by then-President George W. Bush, and Senate Republicans, who were threatening to exercise the majority's prerogative to sustain a ruling cutting off debate on those nominations, thereby establishing a new precedent against judicial filibusters right smack in the middle of the 109th Congress.
And indeed, the standoff did end without such a precedent being established, and with the agreement of the Democratic signatories to the agreement to support cloture on most of the judicial nominations then pending (with two agreed-upon exceptions), and on such nominations yet to come, unless those nominations presented "extraordinary circumstances," though the term was not defined. So perhaps we shouldn't blame folks for coming away from the episode with vague memories of the nuclear option being "defused." And that in turn is probably what's fueling the desire to see a similar agreement forged, to once again defuse today's Senate tensions, and eliminate the "danger" of simple majority rule making.
But if you actually look at the Gang of 14's written agreement—and yes, they did commit their agreement to paper—you'll find that this nostalgic recollection simply isn't borne out by the facts. Rather, the Gang's agreement actually recognized and enshrined the majority's right to exercise the nuclear option. In fact, it was the essential piece of the agreement that gave it it's force.
The relevant text of the agreement, via Wikipedia, appears below:
Part II: Commitments for Future NominationsPart A embodied the commitments of the seven Democratic signatories to the agreement. They agreed to filibuster judicial nominees only under extraordinary circumstances.
A. Future Nominations. Signatories will exercise their responsibilities under the Advice and Consent Clause of the United States Constitution in good faith. Nominees should be filibustered only under extraordinary circumstances, and each signatory must use his or her own discretion and judgment in determining whether such circumstances exist.
B. Rules Changes. In light of the spirit and continuing commitments made in this agreement, we commit to oppose the rules changes in the 109th Congress, which we understand to be any amendment to or interpretation of the Rules of the Senate that would force a vote on a judicial nomination by means other than unanimous consent or Rule XXII.
Part B embodied the commitments of the seven Republican signatories. And they agreed to oppose rules changes (in the 109th Congress, anyway) accomplished by any means other than by unanimous consent or the current cloture rules, that is, where a 2/3 vote would be required to invoke cloture on any proposed change.
So, do we see what this agreement really meant? It did not commit the Republican signatories to opposition in principle to accomplishing rules changes by other means, namely the nuclear option. It simply committed them to withholding their votes in favor of such a procedure, so long as Democrats agreed not to filibuster judicial nominees—and even then, only for the duration of the 109th Congress. Should the Democratic signatories, in the judgment of their Republican peers, have violated their agreement, the Republicans would presumably have been entitled to vote for an exercise of the nuclear option.
That's a far cry from the fantasy version of the Gang of 14 agreement, which people seem to believe somehow undermined the legitimacy of the nuclear and/or constitutional option. Indeed, if the signatories had not recognized its legitimacy, their agreement would have been entirely without force. Democrats would have signed away their right to filibuster judicial nominees in exchange for ... nothing at all. And the penalty for violating the agreement would likewise be ... nothing at all.
Obviously, that's a nonsensical view of the true history of the Gang of 14's agreement. Yes, it's true that it avoided a serious and worrisome confrontation. It's also true that a similar agreement could theoretically do the same today. But the Gang of 14's agreement could not have worked, and no such agreement could work today, unless based on a recognition of the legitimacy of the threat to change the rules by majority vote. Nor would any such agreement today merit any comparison to the Gang of 14's agreement unless it was enforceable against breaches in the same way, that is, by the exercise of the majority's right to end debate on a proposal to change the rules and pass those changes by a simple majority vote.