If the Constitution written in 1776 was being properly enforced, I don't believe that we would need any new amendments and an Article V Convention would be totally unnecessary. Unfortunately, the Supreme Court has amended the Constitution every time they interpret it. The authority to interpret the Constitution was NOT granted to the Supreme Court in the Constitution. Chief Justice John Marshall introduced the doctrine known as Judicial Review. He took the position that the authority of the Supreme Court to interpret the meaning of the Constitution was an implied power that was both necessary and proper.
Allowing the Supreme Court to change the Constitution by interpreting it, gives the Court the power to amend the Constitution without a single state having to ratify it. The Court is a perpetual Convention to Amend the Constitution. Instead of needing two-thirds of Congress and three-fourths of the states to agree, the nine lawyers in black robes need only vote 5-4 to amend the Constituion without the concurrence of a single state.
By using the Principle of Nullification one of the checks and balances that has been lost can be restored and we will have a mechanism where the states can prevent the Supreme Court from distorting the Constitution.