Some people want you to believe that the following statement is "ambiguous"--
Any amendment to, or revision of this Constitution, may be proposed by the Congress upon a vote of three fourths of all its Members;They want you to believe that it is ambiguous because they actually want the Supreme Court to decide what the Constitution means by this simple declarative sentence--after the President gets seven more chances to populate it with willing sycophants.
But it is NOT the case that one of the two alternatives, joint or separate voting on proposed charter changes, is unconstitutional, since either mode can comply with the three fourths majority requirement. Either mode is constitutional. There is naothing for the Supreme Court to decide. It is not that kind of ambiguity. It is up to the Congress to dacecide in its own discretion, which mode to use, not for the Supreme Court to decide which is bigger, half a dozen of one or six of the other!
In my opinion there is NO ambiguity to the fact that "the Congress" (NOT the House, nor the Senate, nor the Members of the Congress) is here granted the power to propose any amendment or revision to the Charter. HOW it is to comply with the three fourths majority rule requirement for approving such proposals is, most emphatically, entirely in the discretion of the Congress. There is no deep or hidden meaning in this plain language for the Supreme Court to debate upon, or discern, or adjudicate. The Constitution simply provides "the Congress" with the power to propose charter changes as long as it obeys the three fourths majority rule.
Thus, it is indubitably Constitutional for the Congress to adopt either VOTING JOINTLY as the House Majority is suddenly insisting upon as a last desperate chachachero dance, or VOTING SEPARATELY as the House and Senate have put in their Rules until this very day! Let me repeat: voting jointly or voting separately complies with the three fourths majority rule, so either mode would be Constitutional.
The important and perhaps subtle point that lots of people have missed, is that the Constitution leaves it entirely up to the Congress HOW it will exercise "constituent power" (the power to propose changes) whilst complying with the numerical majority requirement.
Now for the coup d'grace: although "the Congress" could conceivably decide to adopt the joint voting mode and ignore the difference between Senate and House membership, it can only ever come to this decision by first voting upon it in the default mode by which the Congress does anything--by having the House and Senate separately approve the same by a simple majority vote!
There are in fact a myriad number of ways conceivable for the Congress to approve proposed charter changes whilst complying with the three fourths majority rule. But every single one of these completely Constitutional modes can only be approved by "the Congress" in its default mode: House and Senate voting separately!
So once and for all, ladies and germs: the Supreme Court has nothing to decide or adjudicate in Article 17 Sec. 1. The Constitution is not ambiguous about Charter Change. It gives to the Congress all the powers and prerogatives to decide HOW it will comply with the Constitution when it proposes changes to it.
The "laws of physics" of a Bicameral Legislature dictate the "construction" of the Constitution and cannot be repealed without self-ridicule, not even by a Supreme Court of uniform sycophancy.