This is some of the discussions regarding the issue
The question of whether requiring 60 votes to invoke cloture was constitutional was debated extensively. Lloyd Cutler, former Counsel to President Carter, testified that the requirement for a supermajority is unconstitutional and that the Senate needs to correct this. ``I also submit that the Senate, which is in part a judicial body, has a judicial duty to consider and decide this question. And if a majority of the Senate were to agree that the supermajority requirements are unconstitutional, that same majority can, in my view, and should, amend the rule so that a majority vote would be sufficient to cut off debate.''9 Whether ``filibusters or the supermajority requirements of the rule are desirable or undesirable is beside the point,'' he continued.10
Mr. Cutler offered several arguments in support of his assertion, including the absence in the Constitution of ending debate among the cases where a supermajority is needed to take action. Also, he cited the quorum clause of the Constitution which states that a majority shall constitute a quorum to do business. ``For the Senate to adopt a rule, as it has, requiring the affirmative vote of 60 Senators to pass such a motion clearly violates the quorum clause of the Constitution...It means a supermajority of at least 61 Senators...must be present as the quorum to do the business of voting on the cloture motion and that 60 of them must be present to vote for cloture. That is a plain violation of the quorum provision of the Constitution itself.''11 Some Members countered that because the Constitution allows each House to determine the rules of its proceedings, the Senate may adopt a rule requiring a supermajority to invoke cloture.
Former Vice President Walter Mondale, the last witness to appear before the Joint Committee, spoke against major changes in the cloture rule but also warned that indiscriminate use of dilatory tactics might force changes in long-standing Senate traditions. ``I continue to support the current rules governing filibusters. I helped lead the fight to bring about the current 60-vote threshold. The reason I still stick with the need, though, is that I went through a time when I think American liberty was under threat. I went through a time here when wars were being started without the knowledge of the Senate. I went through a time here when money was being spent or impounded illegally . . . A lot of us found the ability to ventilate an issue, to get it out, to debate it, to stall everything, to be essential. There was no other place to go, really . . . No other institution in our system can perform this task. On the other hand, the increasing use of the filibuster on what appear to be normal, even routine, legislative issues may be weakening public support for this instrument...If Members continue to use the filibuster to fight over issues that are most appropriately resolved through simple majority vote, the body may soon find itself under pressure to get rid of this important protection, and I believe that would be a tragedy.''12
Holds
Another focus of attention pertained to the use of holds to delay or prevent items from being called up for consideration. In favor of limiting the use of holds, some argued that a historical Senate courtesy of temporary delay is being abused, with Senators using blanket holds for a number of bills, keeping holds on bills indefinitely, and using holds to retaliate against colleagues who have not supported their legislation. Sometimes staff put holds on bills and Senators do not know about it, some Senators asserted. On the problem of holds, Senator James Exon of Nebraska testified that ``the Senate time and time again has been tied into knots with the whole procedure [of holds], especially near the end of a session by the current ability of one Senator to stop a bill from proceeding by unanimous consent through the threat of an extended debate.''13
Several suggestions for limiting the use of holds were put forth. Senator Exon proposed requiring 16 Senators to place a hold on a bill, just as 16 Senators must sign a cloture petition before it can be filed, since a hold is a form of ``reverse cloture.'' Professor Smith stated that five objections, rather than one, should be required to object to a floor leader's request to call up a measure (as well as a request to limit debate or amendments.) Others said that the names of Senators placing holds should be made public, to enable Senators to work out their differences on relevant matters. Still others advocated imposing a time limit during which holds would be in effect. Rather than reform the hold itself, Senator Pete Domenici of New Mexico, Joint Committee Co-Vice-Chairman, noted that the Senate will go a long way towards eliminating holds by eliminating or reducing debate on the motion to proceed. Finally, some asserted that no change to the rules is needed; rather, what is necessary is the determination to proceed, and the Majority Leader should proceed with calling up items for consideration.
I think this is in this link..